Updated openstack/openstack
Project: openstack/ceilometer  35c20612ca1de176ffdc15ec509df051c5b723ee

Workflow documentation is now in infra-manual

Replace URLs for workflow documentation to appropriate parts of the
OpenStack Project Infrastructure Manual.

Change-Id: Ia5d22c51f2f84b5c70af855f6f5fe7b8d7d89586