Make test_quota work with CONF.use_neutron=True by default
Make test_quota work with CONF.use_neutron=True by default

There were a couple of nova-network specific floating IP quota
tests in here that needed to be isolated. Plus we need to mock
out the validate_networks network API which for Neutron does a
port quota check when creating instances. Since none of the
tests in here care about that, we just mock it out.

Part of blueprint use-neutron-by-default

Change-Id: Id29326de8337aa0472d537cfe2b8880e90ed7774

mikalstill/nova,Juniper/nova,klmitch/nova,openstack/nova,rahulunair/nova,mahak/nova,gooddata/openstack-nova,rajalokan/nova,klmitch/nova,mikalstill/nova,hanlind/nova,rajalokan/nova,mahak/nova,gooddata/openstack-nova,vmturbo/nova,vmturbo/nova,hanlind/nova,gooddata/openstack-nova,gooddata/openstack-nova,rahulunair/nova,Juniper/nova,phenoxim/nova,rahulunair/nova,hanlind/nova,phenoxim/nova,mahak/nova,jianghuaw/nova,openstack/nova,klmitch/nova,jianghuaw/nova,vmturbo/nova,Juniper/nova,openstack/nova,mikalstill/nova,rajalokan/nova,klmitch/nova,vmturbo/nova,jianghuaw/nova,Juniper/nova,jianghuaw/nova,rajalokan/nova