Correction of tunnel_types config option in values.yaml, regarding the
_openvswitch_agent.ini.tpl layout.
Added bridge mappings, since it was lost with auto-generate configs.
Removed br-physnet1 and physnet1 in favor of 'external' network config.
Removed default network interface, replacing it with search for interface
with default gateway for tunneling. The interface for external bridge
has to be defined explicitly, otherwise no interface will be added to
external bridge automatically.
In OVS configuration scripts, added handling null port passed.
Change-Id: I90ebe222323b3b1ec8d20a8038c0dfed3de9b58c
Closes-Bug: #1686365
Closes-Bug: #1686367
a378304490