Separating skins from core MediaWiki

by Bartosz Dziewoński for Wikimedia

I intend to separate core skins out of MediaWiki, removing cross-dependencies with MediaWiki itself, and making it possible for non-core skins to have all of the capabilities of core ones. As a prerequisite, I wish to simplify the skin creation, packaging and (un)installation. This would make the lives of both skin creators and site administrators wishing to use a non-default skin a lot easier. If everything goes well, the core skins will be moved out of core, to separate git repositories.