* Added in-base logging through a foreign data wrapper, which is only
possible using PostgreSQL 9.1
* Renamed database-related configuration files to indicate that they are
samples, and added the "real" names to the Git ignore list. Server
distribution modified accordingly.
* Removed PL/PgSQL registration (it was only necessary on 8.4)
* Added pgTAP SQL definitions and a script which will (hopefully) be
executed by the build system after the main Java build in order to
execute database unit tests. The script supports both admin- and user-
level testing. I also added a few tests to make sure the testing framework
actually runs them.
* Added documentation about the database definitions structure
