relax version bounds on cryptohash and http-conduit

Conflicts:
	aws.cabal
SimpleDb: aws sez "consistent error message formats are for suckers"
Failure-0.1.2 was insufficient on my (unevenly-updated) system.
release 0.7.6
case-insensitive 1.0, http-types 0.8.0
Merge branch 'stable'