Updated mediawiki/extensions
Project: mediawiki/extensions/MultimediaViewer  53da285b07b70799eb4957fda7e3f860acf1ee71

Merge MultiLightbox into MultimediaViewer

* merges parent classes into child classes
* moves some files and tests to have a consistent directory structure

Change-Id: I360cc0805d8a561f5105fb063747457f67e1fccd
Mingle: https://wikimedia.mingle.thoughtworks.com/projects/multimedia/cards/177