Updated mediawiki/extensions
Project: mediawiki/extensions/MultimediaViewer  8024d98e71d636eb5d7c7c0477ac9f94a9d186c6

Move providers into their own subdirectory

Also refactor MultimediaViewer.php a bit to get rid of all the globals.

Mingle: https://wikimedia.mingle.thoughtworks.com/projects/multimedia/cards/123
Change-Id: Ieca4263ecc7652dc6bc36db63b99d3813c4653e4