* 'cλash' of http://git.stderr.nl/matthijs/projects/master-project:
Make letflat work for nonrec lets in rec lets as well.
Revert "Limit flattenLets to non-recursive lets only."
Disable letmerge.
Make letremoveunused work for recursive lets again.
Make letflat work for recursive lets again.
Turn of Normalize debugging again, accidentally committed.