Add all-in-one node definition

Adds an all-in-one node class definition to core.pp and a
corresponding example node definition in site.pp.  This allows
creation of a node that runs all basic OpenStack functions.

Implements: blueprint openstack-all-in-one
Add glance backend support to all-in-one

Previously only the file backend could be used for all-in-one
deployments because we weren't passing the glance_backend
parameter to the openstack::all class.  This commit fixes that
so that we pass the parameter appropriately, allowing users to
specify other backends (such as rbd).

Implements: blueprint openstack-all-in-one
Merge pull request #175 from CiscoSystems/bp/openstack-all-in-one

Add all-in-one node definition