Whitespace
Fix the ‘--prebuilt-only’ flag
Test the ‘--prebuilt-only’ flag
nix-env: Install all outputs of a derivation

If you explicitly install a package, presumably you want all of it.
So symlink all outputs in the user environment.
Add a test for ‘nix-env --set-flag active ...’
buildenv.pl: Create symlinks in priority order

This reduces unnecessary symlink/unlink steps.
Test priorities
Document multiple output support
nix-channel --update needs bzip2
Document new primops
Tiny optimisation in the filter primop
Updated release notes
Build Debs for Ubuntu 12.10
Produce an xz-compressed tarball

Footnote: doing "make dist-gzip dist-xz" doesn't work with Automake;
you have to do "make dist-gzip; dist-xz".  That's because the dist-*
targets delete the temporary distdir at the end.
Support xz compression of nixexprs.tar in channels
Add release date
Fix RPM build

http://hydra.nixos.org/build/3436511
Typo
Add a dependency on xz
Add a dependency on xz-utils