[TAP] Remake TAPFactory into an abstract class + let limit the number of jobs (async and sync) by allowing the TAPFactory to communicate with a connection pool

[TAP] Remove all generic types + Delete specific (for ResultSet) output formatters + Modify the main output formatter

TAP: Fix incorrect XML format: the INFO for PROVIDER was not ended properly => an error was raised by TOPCAT when a Java error was occuring in TAP or in a query execution.