"Initial" version of SiteScout, compatible with MW 1.23+

SiteScout, a social & simplified version of Special:RecentChanges, has
been around since 2006 or so and two older iterations can be found in the
interwebs, but this is the first time SiteScout's been committed to an
official MediaWiki code repository, hence the "quotes" around "initial".

Change-Id: Id8d5b1d307759df63eeede10d29f666c9dafe3b7