Added the necessary database code to convert the contents of event
queues into actual event records. The changes include:
* a new table, events.pending_events, which is automatically filled by
a trigger when events are inserted into queue tables,
* the game.events.batchSize constant which defines the maximal amount
of events to process in a single transaction,
* the events.eq_process() stored procedure, which processes the events.
In addition, the "hstore" extension was added as it is the easiest way
to convert events from the queues' table model to the store's
meta-model.
* Added user mapping on the "remote" logging database for the
administrative user. This allows calls to sys.write_sql_log() to succeed
when they are executed by code with administrative privileges.
* Added test suites for both the link to the database and the function
itself.
* Replaced RAISE NOTICE with actual logging in the universe generator
* The main loader script has been updated to generate the list of files
it needs to load automatically. As a consequence, files that contained
manually-maintained lists of scripts have been removed, and definition
directories have been renamed accordingly.
* PostgreSQL extension loading and configuration has been moved to a
separate script to be loaded automatically in the main transaction.
* Data and function definition scripts that had the -data or -functions
suffix have been renamed (the suffix is unnecessary).
* Unit tests have been reorganised to follow the definition's structure.
* Documentation has been improved
