Add endpoint_type parameter to MetaInterfaceDriver

Previously MetaInterfaceDriver communicates with neutron-server
via 'publicURL' because it uses python-neutronclient without
endpoint_type and 'publicURL' is the default.
It causes error when a user intends to use internal or admin URL
for communication between MetaInterfaceDriver and neutron-server.

Change-Id: Id321d5a16a08a4bda618f98bb1eb7cb1b0b9eb08
Closes-bug: #1354285
Merge "Add endpoint_type parameter to MetaInterfaceDriver"