Starting update to MediaWiki 1.23

* This is the start of the update to MediaWiki 1.23.
* It will fix seval issue where wikia had to apply the fix. which is no longer needed.
* It also updates languges and resource loader and moved the files into lib and src.

Change-Id: I06dd996b8c9acee9dd4c58b61b8e2d83e367b1cf
Merge remote-tracking branch 'origin' into dev

Change-Id: I054f1ace82173cd2ee5fe2df3a7a000039f2da65