Fixes <xi:include> and removes <xi:fallback>

Changes the location point <xi:include> to git.openstack.org
as it is a more reliable source for OpenStack projects.

Change-Id: I399dac6bd85dd53d65415cf9f05bc9dd1b087d88
Partial-Bug: #1338678
Merge "Fixes <xi:include> and removes <xi:fallback>"