Merge branch 'features/postgresql' into develop

- add spack cd command.
- Fix bug in modules hook

Conflicts:
	lib/spack/spack/cmd/stage.py
	lib/spack/spack/hooks/dotkit.py
	share/spack/setup-env.bash

share/spack/csh/spack.csh

@@ -45,6 +45,10 @@ set _sp_spec=""
 # Figure out what type of module we're running here.
 set _sp_modtype = ""
 switch ($_sp_subcommand)
+case "cd":
+    shift _sp_args
+    cd `spack stage --print-build-dir $_sp_args`
+    breaksw
 case use:
 case unuse:
 case load: