Title: Controlling the VNC Proxy service

Describe the issue:
The get-vnc-console CLI command, and the dashboard vnc console hangs because it is not mentioned that we need to enable, and install the consoleauth service, which is part of the openstack-nova-console package.

I got errors like this in /var/log/nova/api.log:
2013-07-04 18:13:49.664 ERROR nova.api.openstack [req-6e7c8239-57e4-4a07-b915-6966af2db13f 0845d8bcf6c9453e9cb63e15bd07cce3 0462cfe859364e2e92a1f78309576d02] Caught error: Timeout while waiting on RPC response.
[..]
2013-07-04 18:13:49.664 17690 TRACE nova.api.openstack Timeout: Timeout while waiting on RPC response.

Suggestions for improvement:
1. Suggest to install openstack-nova-console package
2. Enable openstack-nova-consoleauth service and make it start automatically.

# yum install openstack-nova-console
# service openstack-nova-consoleauth start
# chkconfig openstack-nova-consoleauth on

Additional information:

This is documented here too:
http://docs.openstack.org/trunk/openstack-compute/admin/content/faq-about-vnc.html

Q: When I use nova get-vnc-console or click on the VNC tab of the Dashboard, it hangs. Why?

A: Make sure you are running nova-consoleauth (in addition to nova-novncproxy). The proxies rely on nova-consoleauth to validate tokens, and waits for a reply from them until a timeout is reached.