Set $wgCategoryCollation to 'uca-cs' on cswiki

Doing just that; will need a shell user to rebuild
category sort keys for the setting to work.

Bug: 64885
Change-Id: If6992ff516818fc267c2d9baf9212315b69f6d1b
Merge "Set $wgCategoryCollation to 'uca-cs' on cswiki"