Merge pull request #331 from vuntz/release/roxy/master

Moved role constraints into model and removed edit deployment
Fix to work when keystone is behind haproxy
Use new helpers to get hostnames for endpoints
HAProxy support for nova controller
Use correct glance/neutron host when glance/neutron is behind haproxy
Do not accept setting up shared storage when a cluster is used

It makes no sense to have shared storage when the controller is a
cluster, since shared storage will not be HA.
We don't use Opscode::OpenSSL::Password anymore
Stop hardcoding ports in several places

Using default attributes is just safer.