Add support to linuxbridge manifests for Red Hat distros

This mirrors the change that was done for the OVS plugin/agent.
In addition, defaults for sql_connection and network_vlan_ranges
that mirror the ones for the OVS plugin were added.

Change-Id: I56c6373215bb3940c870f5921c70b197b4fe74f1
Add LBaaS Support

Since OpenStack Quantum has a LBaaS agent in Grizzly release,
this patch install and configure it with the default driver : HAproxy.

Change-Id: I68af63c33f6f5cd712a66dc747d3da8d01222aeb
Lookup tenant id via keystone_tenant.instances

 * Previously tenant_id was being looked up via the catalog,
   but that precludes the tenant being created in the same run
   as the quantum resource.  Using instances ensures that the id
   can always be looked up by the name.

Change-Id: I038edc10e38c4edacb4f40c446bf75156b2af882
Add quantum_l3_ovs_bridge custom type.

 * The type and associated provider manages whether the gateway ip
   of a subnet is configured on a target ovs bridge.

Change-Id: I7622dcc1e396a1ab0608a4f4fda610a7cf08e6fa
Merge "Lookup tenant id via keystone_tenant.instances"
Merge "Add quantum_l3_ovs_bridge custom type."
Merge "Add support to linuxbridge manifests for Red Hat distros"
Remove native type prefetches

The network, router, subnet and router interface
providers attempt to prefetch the configuration,
which can result in empty or stale values being
loaded as quantum configuration. The former will
result in errors stating the quantum.conf file
is incomplete, while the latter will often
result in authentication errors.

This patch removes the prefetching in the child
classes and explicitly sets the conf to nil in
the parent quantum provider so that it will be
loaded at the correct time.

Change-Id: Ia2dbc8b687498be96d09c9286fb3f07e0c5b8f96
bug 1197588