Update for MW 1.21

Rewrite the MW interface to call functions directly instead of going through
the external API.  Also add an 'edit all' tab to category pages and
Special:WhatLinksHere for quick access.

Change-Id: I2ea197d797253b33809a353fd21a633c0347654b
Signed-off-by: Adam Nielsen <malvineous@shikadi.net>