Adds Heat and external network support

Adds Heat and external network support

Patch changes behavior to do the following
External Network:
 - openvswitch is now installed at the beginning of the puppet run
 - public interface config is changed to be an ovsport on br-ex
 - br-ex is created with the IP address formerly on public interface
 - neutron is configured to use br-ex
 - after neutron is running, an external  provider_network and
       provider_subnet are created
New global parameters required (only if external_network_flag is true):
 - public_gateway
 - public_dns
 - public_network
 - public_subnet
 - public_allocation_start
 - public_allocation_end

Heat is now in HA and added to deployment by default:
Introduces 6 new required global params:
 - heat_admin_vip
 - heat_private_vip
 - heat_public_vip
 - heat_cfn_admin_vip
 - heat_cfn_private_vip
 - heat_cfn_public_vip

JIRA: BGS-31

Change-Id: Ic4428b31c2a3028aa46c4da73e4d0f338b6651d3
Signed-off-by: Tim Rozet <trozet@redhat.com>