of Hydra builds more distinct (e.g. "patchelf-build-0.5pre1234"
instead of just "patchelf-build"). If the version isn't known,
append at least the revision.
* Propagate the release name of the source tarball to Nix builds.
Useful to provide sensible package names in channels.
svn path=/nixpkgs/trunk/; revision=14294