Add $config['db']['annotate_queries'] option to include caller ID comments into queri...

Add $config['db']['annotate_queries'] option to include caller ID comments into queries. Comment can then be seen in process list, slow query logs on the server, aiding in tracking down unexpected slow queries.

SELECT /* queuedaemon.php Ostatus_profile->processPost */ * FROM notice WHERE ( notice.uri = 'http://stormcloud.local/mublog2/notice/479' )
INSERT /* POST Notice::saveNew */ INTO notice (profile_id , content ....