Merge branch 'features/newarch' into develop

Conflicts:
	lib/spack/spack/config.py
	var/spack/repos/builtin/packages/lua/package.py

var/spack/repos/builtin/packages/boost/package.py

@@ -132,7 +132,7 @@ def url_for_version(self, version):
                "/boost/%s/boost_%s.tar.bz2" % (dots, underscores)
 
     def determine_toolset(self, spec):
-        if spec.satisfies("arch=darwin-x86_64"):
+        if spec.satisfies("platform=darwin"):
             return 'darwin'
 
         toolsets = {'g++': 'gcc',