Neutron ML2 template fix
Neutron ML2 template fix

Neutron fails to deploy if neutron_provider_networks.network_flat_networks
or neutron_provider_networks.network_vlan_ranges are not set.

This will fix that by making these template sections 'if defined'

Change-Id: I4fcc542a7177e9a84302fae03731dad044bf947c
Closes-Bug: #1535498

michaelgugino/openstack-ansible-os_neutron,michaelgugino/openstack-ansible-os_neutron