A JUnit test case has been added in order to check that all possible phase
transitions are respecting the UWS-1.1 standard. However, there is anyway
a bit more freedom for some of them:

    - it is possible to go to and come from UNKNOWN at any time, whatever is
	  the source or target phase.

	- it is possible to go to ERROR or ABORTED from the phases HELD and
	  SUSPENDED. This fact was not specified in the State Machine figure of the
	  UWS standard but the following sentence at section
	  "2.1.3 Execution Phase" (page 7) should allow that:
	  "At any time before the COMPLETED phase a job may either be ABORTED or
	   may suffer an ERROR."

	- the UWS-1.1 document has an inconsistency about the HELD phase. At
	  section "2.1.3 Execution Phase" (page 7), the following sentence implies
	  that it is only possible to go to HELD from PENDING (because it would not
	  be possible to queue the job). And so, when PHASE=RUN is sent by the UWS
      client, if now possible, the job should go in phase QUEUED. However the
	  State Machine figure suggests that it is possible to go to HELD only from
	  EXECUTING and that a PHASE=RUN would make the job go back to EXECUTING (if
	  now possible). Because of this inconsistency, the UWSLibrary made possible
	  the following transitions: PENDING/EXECUTING->HELD->QUEUED/EXECUTING.

(note: a figure illustrating the phase transitions supported by the
       UWSLibrary-4.3 has been created in the directory `img` of the
	   UWS-Tutorial website under the file name `state_machine.png`...which of
	   course will be visible only when uwslib-4.3 will be released)

Besides, this commit also include almost a full rewriting of the Javadoc of
JobPhase and ExecutionPhase. The Javadoc of UWSJob has just been reformated
so that comments do not exceed 80 (+2) characters. This reformating aims to
improve the human reading of the Javadoc while looking at the source files ;
however this should not affect much the HTML version of the Javadoc.

This property is displayed in the XML and JSON serialization of a job item.
It is also backuped and restored from a UWS backup file.

/!\ WARNING: Small modification of the API! Since creationTime must be
             set by the UWS service at creation of a job, this date must also
             be imported at backup restoration. Hence the modification of the
             interface uws.service.UWSFactory and its implementations
             (particularly tap.AbstractTAPFactory). Similarly the class
             uws.job.UWSJob and tap.job.TAPJob have underwent exactly the same
             modification in one of their constructors.

This commit also adds the new optional jobRef items: creationTime, runID and
ownerID in the XML and JSON serializations.

<job>.

This commit also:

    - set the version of the UWS protocol to 1.1 (cf UWS.VERSION)
	- add a static constant for the standardID (cf UWS.STANDARD_ID)
	- add a xlink:type and xlink:href for jobListRef in the uws XML
	- set the @version Javadoc attribute of all modified classes to 4.3
	  (scheduled version of the UWSLibrary supporting UWS-1.1)

serialization of all results if such information are available.

This commit also fix few comments about the result's XML serialization.

The processing of xlink:type of a result reference is made similar as the one of
jobRef.

Although the Java code allowed the specification of a description of a User
Defined Function, it was not possible to set one in the UDFs listed in the
configuration file.

This commit fixes a typo introduced in the commit
09ee79c4 ; because of that the VOTable's COOSYS
was not added anymore in query results.

in the TAP configuration file.

Now, JDBCConnection is fully capable to test the existence of schemas, tables
and columns of a MySQL database. Thanks to @zonia3000 for solving this issue.

Merge pull request #59 from zonia3000/master

* The parsing did not allow unsigned numerics and SQL SET functions as
  specified in the ADQL 2.0 grammar

* It was even forbidden to put a column whose the type is not String.

* The translation of a concatenation expression was always prefixed by the
  ADQLList's name: CONCAT_STR. Of course, no database likes that...

Regarding this last point, this commit fixes the GitHub issue #54

This commit fixes the Github issue #58

if the alias is not delimited in ADQL.

This commit fixes the GitHub issue #56

are translated: the table part (if a reference to an aliased table) should be
as declared in the DBTable (especially now that we have DBTableAlias to deal
nicely with table aliases).

this table is declared with an alias. Instead, the table alias must be used.

Note: This problem occurred only when ADQLParser was used with a DBChecker.

This commit fixes the GitHub issue #53

The order of its children was incorrect according to the XSD schema:
the 'fkColumn' must be written before 'description' and 'utype'.

A delimited identifier is any sequence of characters between a pair of
double quotes. For instance: "123 I am a delimited identifier!".

It is of course possible to have double quotes inside this kind of identifier,
but they have to be doubled in order to not be mistaken with the end of the
identifier. For instance: "Cool ""identifier""".

However, this escape option was not taken into account by the ADQL library,
though the same mechanism was already in place for string contants.

This commit also includes the 2 following points:

    - for (really really tiny) optimisation purpose, replace String by a
	  char when there is only one character to append to a StringBuffer

	- add a bit more details about Result.type in the Javadoc (it should be
	  a xlink:type and not a random custom type)

Until now, it was possible to destroy the job by posting ACTION=DELETE
with a URL like below:

    {root-uws}/{job-list}/{job-id}/foo/bar

That is completely wrong. The correct URL for this action must always be:

    {root-uws}/{job-list}/{job-id}

This commit fixes this error in UWSServlet and UWSService.

The configuration of the DestructionTimeController was never effective
in the UWSServlet with a configuration file: the wrong instance was set.

synchronized although the collection of observers is synchronized (Vector) ;
using an Iterator ensures the synchronization and avoids concurrency problems.

  - uws.service.UWS.VERSION  (static final)
  - tap.resource.TAP.VERSION (static final)

Dealing with several protocol versions in the same time is quite difficult and
may significantly alter the libraries API in an unstable way. That's why, for
the TAP and UWS libraries, only one version is implemented (i.e. the last one).
To use a older version of the protocol, one must use an older version of the
corresponding library.

About the versioning of the ADQL standard, there is no need to set any version
number somewhere because a different ADQL version implies a different grammar.
It means that a different parser is required for each ADQL version. For the
moment, there is only one version, so no need to change anything to the ADQL
library about ADQL version. Later, ADQLParser should become an interface and
a factory will have to be used in order to get the parser corresponding to the
desired ADQL version.

in TAP_SCHEMA.

RegTAP is detected successfully if the schema 'rr' exists (case sensitive)
and contains at least the following tables (names also case sensitive):
	- capability
	- interface
	- intf_param
	- relationship
	- res_date
	- res_detail
	- res_role
	- res_schema
	- res_subject
	- res_table
	- resource
	- table_column
	- validation

The table name can be prefixed by 'rr' (case sensitive) or not. For instance:
'rr.capability' and 'capability' are both detected successfully.

All these constraints (including the case sensitive one) are based on the
requirements of the RegTAP-1.0 standard document. They are set in order
to not declare the RegTAP DM by accident AND to provide a first low
validation of the RegTAP schema and tables. Low validation because
columns (as well as datatype, utypes, indices and UDF functions) are
never checked.

This commit resolves the GitHub issue #51

standard table. The same for the additional column
TAP_SCHEMA.columns.coosys_id.

coordinate system of coordinate columns.
  (see the HTML page src/tap/metadata/tap_coosys.html for more details)

This commit is a merge with the branch 'coosys'

in the TAP metadata.

This help will be later used in the complete documentation of the TAPLibrary.

This commit resolves partially the issue #28

Ideally, there should be an implementation of UWSLog and TAPLog working with
Log4j and another for SLF4J (and eventually for other logging mechanism).
Additionally, an implementation storing log messages in database would be
interesting. All these ideas may be implemented in UWSLib and TAPLib in a
future version.

_This commit aims to fix the issue #47_

reserved word is encountered instead of a column/table/schema name/alias.

On the contrary to the previous commit, this time a list of SQL reserved words
has been added into the ADQL grammar. In this way, the parser will ensure that
no word of this list is used in an ADQL query. The raised error is then enriched
of an HINT message stating that this word is part of SQL, is not supported
by ADQL and must be written between double quotes if used as an identifier.

The list of SQL reserved words comes from the ADQL-2.0 standard, after removal
of all potentially used ADQL words, in order to avoid a conflict with the
already existing tokens in the ADQL grammar.

reserved word is encountered instead of a column/table/schema name/alias.

No list of ADQL reserved words has been added into the ADQL grammar.

However, the ADQL grammar has been slightly changed in order to provide a more
precise location of the REAL wrong part of the query.

Before this commit, if an ADQL reserved word (e.g. 'point') was encountered
outside of its normal syntax (e.g. 'point' no followed by an opening
parenthesis), the next token was highlighted instead of this one. Hence a
confusing error message.

For instance, the following ADQL query:

```sql
SELECT point
FROM aTable
```

returned the following error message:

> Encountered "FROM". Was expecting: "("

Now, it will return the following one:

> Encountered "point". Was expecting one of: "*" <QUANTIFIER> "TOP" [...]
> (HINT: "point" is a reserved ADQL word. To use it as a column/table/schema name/alias, write it between double quotes.)

This error message highlights exactly the source of the problem and even provide
to the user a clear explanation of why the query did not parse and how it could
be solved.

with a different local charset, the error message will print differently the
incorrect character.

The idea is to get rid of special characters such as '-', '+' , '(', ...

This commit resolves a part of the Pull Request #14

and HashMap more generic by returning resp. a List and Map instead.

This commit resolves a part of the Pull Request #14