Exclude another IDE config directory from the jar
Issue #1: fix Gerrit plugin reload

Wicket's storing state per session gets in the way. Especially its
attaching Java objects to the HTTP session.

Also really disable that GitBlit ticket service. Turns out that in
GitBlit 1.6.1, the "null ticket service" is not a "null" implementation
but instead is doing things, and then crashes. Replaced by a real
stubbed implementation that really does nothing.

Finally, fix a copy-paste error in the license headers.