Remove explicit dependency on amqplib
Remove explicit dependency on amqplib

kombu already depends on amqp or amqplib depending on its
version, and no explicit access to amqplib exists in neutron code.

Closes-Bug: #1317094
Change-Id: I5cf189d7173b732cba6df3f9b6aff1d2bb85cdfe

openstack/neutron-vpnaas,dougwig/x-neutron-vpnaas,citrix-openstack-build/neutron-vpnaas,openstack/neutron-vpnaas