Version improvement

Added 2 functionalities:
  1) when installed from a development ubuntu package (nightly-build or hand made) --version return the complete package version (e.g. "1.0.0-2+dev1389172584-9281123")
  2) when installed directly from git --version return the current version with a "-git<hash>" suffix (e.g. "1.0.0-git10075f1")