[Hawkular-dev] Version endpoint for components

Hey, I think it would be good for all components that have a REST interface to have a /version endpoint that responds on GET and which returns - the tag (e.g. 0.8.1.Final or 0.3.44-SNAPSHOT or 1.2.3-src-dep-0xcafebabe)) - the git hash they are built from (less needed for .Final) So that clients can easily verify what version they have as peer.