Revert "MonoBook: Use SkinFactory"

This reverts commit c3e1a7fa597b51eb2e516e0e5005d6968d98ede7.

Doing it this way is unnecessarily backwards-incompatible,
and there's probably a nicer way to do this.

Change-Id: Iaceeb01526004de006b4f6cb708d1e947e59090c
Merge "Revert "MonoBook: Use SkinFactory""