Wrong module name checked in language load
Performance tweaks

Switch to MyISAM tables across the board. gwiki_pages and 
gwiki_pageids performed significanly better in testing as MyISAM
so just switching all for consistency.

Add more indexes to gwiki_pages to keep blocks snappy
Performance tweak

Should be exactly the same, and much less expensive, especially 
if gwiki_pages is partitioned
A little bit of polishing on random page block option