tarballs and converts some of the common/Make.rules targets to get
version information from bzr. As part of this, the tarball generation
creates a .stamp_rev file in the common directory which contains both
the name of the bzr repo exported from as well as the revision.
slow) for getting a clean export of the source. But too many of the
packages make some assumptions that they're in a checked out svn tree
that a lot of the auto-rpm building infrastructure breaks. Use at your
own risk.