Merge branch 'fc/remote-bzr'

New remote helper for bzr, with minimum fix squashed in.

* fc/remote-bzr:
  remote-bzr: detect local repositories
  remote-bzr: add support for older versions of bzr
  remote-bzr: add support to push special modes
  remote-bzr: add support for fecthing special modes
  remote-bzr: add simple tests
  remote-bzr: update working tree upon pushing
  remote-bzr: add support for remote repositories
  remote-bzr: add support for pushing
  Add new remote-bzr transport helper