[TAP,ADQL] Improve and remake a part of the database connection. Missing javadoc has been added when missing in the modified tables.

[TAP] Replace Savot by STIL + Change datatype management in TAPColumn (vot-type is no more available from here), TAPType (no votable type inside it) and VotType (can now be created from a TAPType instance + a VotType instance can be converted easily in a TAPType object)

[TAP] Remove TAPTypes and create a new class to represent a TAP column type: TAPType. + Improve the conversion between VOTable type and TAP type by embedding it in TAPType. + Modify TAPColumn in order to integrate TAPType and that its VotType is just a conversion of a TAPType. {This commit is not compilable.}