Move service plugin aliases from neutron to neutron-vpnaas
Move service plugin aliases from neutron to neutron-vpnaas

The aliases should be maintained in the same repo that hosts the plugin
itself.

Change-Id: Ieb4e9fce9f5cf9b5a60f1207ec38a59adfe400a8
Depends-On: I2136a530a8351cc290418d9ae18af08b480707c5

openstack/neutron-vpnaas,openstack/neutron-vpnaas