fixes #1509 - Foreman should use the proxy to import puppet classes

fixes #1324 - Separate permssions on hosts from permissions for objects within hosts.

This allows a user to be granted permission to edit the host (and so change the group or proxy) but not, for example, edit the parameters
This could probably be extended further if necessary.

fixes #1446 - expire idle web sessions

fixes #1281 - assingn more than one domains to a subnet

fixes #402 - Add noops/pending to metric handling, and provide pending hosts for dashboard views.

This change adds the ability to see noops in metric reports inside
foreman graphs, charts and lists. The business reason for this is to allow
users to run their puppet agents in noop mode, and see where nodes have...

WIP rails3 migration

fixes #1257 - various fixes around bcm dhcp record

fixes #724 - Allow default VM specs to be tied to a hostgroup

fixes #762 - Check class assignment consistency

fixes #1077 - Ensure that host OS attributes are related to the OS itself