Move manila repos from stackforge to openstack

According to openstack/governance change
I8010cd03c4d409a7a0532f7963a55b8456877ae1 the acceptance of the
Shared File Systems program's application on August 26 implies its
projects' Git repositories should be within the official namespace.

Change-Id: I41c13866fb085d5833cedaec9b14ed3e3396f5a0
Merge "Move manila repos from stackforge to openstack"