Updated mediawiki/extensions
Project: mediawiki/extensions/MobileFrontend  cb5e26fb4fc122e16c2a84c9973816445d8bc458

Hygiene: Use RL generated CSS

Adjust Makefile to generate the css file separately via load.php
Kill wgMFMobileImageRootDir and make Juliusz happy
Add stable class to body to deal with current transitional state of
chrome header.

Change-Id: I4ed96bf49f4ae26c85b0d8a901446695a089a0db