Updated openstack/openstack
Project: openstack-dev/devstack  a7a2b883b28a6a2137f9b56be956a5d3798a0479

Add and document $NOVA_VNC_ENABLED for forcing VNC on

This allows multinode setups to function correctly without enabling the
unneeded n-novnc and n-xvnc services on pure compute nodes.

Change-Id: Ie02734bb598d27560cf5d674c9e1d9b8dca3801f
Closes-Bug: 1342155