only set network_vlan_ranges for vlan network types

This commit updates the quantum module to ensure
that vlan specific configuration is only applied
when the tenant_network_type is vlan or flat.

it also adds tests that were previously missing from
quantum_plugins_ovs_spec.rb.

Change-Id: I97cffff55ad6ff6cb683efc282e0db46d4687c1a
Merge "only set network_vlan_ranges for vlan network types"