semantic version support + special casing old versions, offline builds, not svn

* Added support in the newer releases (1.23.0-rc.1 and forward) for
  Semantic Versioning.

  This also involved special casing so that diffs with older versions
  (1.23.0rc0 and before) that didn't use semantic versioning.

* Added support for offline creation of tarballs with "--offline"
  option.  Used this while flying back from Zűrich.

* Switched "trunk" which was left over from svn to "master" for the
  new git awesomeness.

Change-Id: I6fbe8b07572a64204673e2491d56e2199b2df40a