The JGit team is now publishing 0.12.1 artifacts on the Eclipse Maven
site. Yeah! That was the last missing piece for a slick Git:Blit
deployment. The build has been reworked to download from Eclipse and
to also download source and javadoc jars for setting up a development
environment.

Made the log4j pattern configurable by operating system.
Moved Markdown utils to their own class since I need StringUtils for
Build and that introduced a chicken-and-egg scenario.

Right now the implementation is hard-coded to pass the realm into a
singleton.  This won't work for a WAR distribution so I will
need to figure out how to properly authenticate the webapp using form
authentication and the git servlet using basic authentication - host
against the same realm.

Change-Id: Ifce000c85c8947c3a768e782c841e41a8953d314