Clean up MySQLPageGenerator

Since we get the database name directly from the site,
it probably doesn't match up with the replicated copy
that is being used (Toolserver or WMF labs).

Also try using oursql if available, it generally has
better unicode support.

Change-Id: Ied3e7b3441ce0b6af500ae9ac6c75c1ba92e13f1
Merge "Clean up MySQLPageGenerator"