Updated openstack/openstack
Project: openstack/nova  cd8603b5003f06b41f27aba81bb62eb4d6f3f8d9

Update devref

* Devref mentioned 10.10 instead of 14.04 as the tested ubuntu
  environment
* Point to our official git mirror instead of github

Change-Id: I4514faeaebe200a2f616bc37fca02c2927edf599