Description of ML2 VXLN configuration options

Configuration option = Default value	Description
[ml2_type_vxlan]
vni_ranges =	(ListOpt) Comma-separated list of <vni_min>:<vni_max> tuples enumerating ranges of VXLAN VNI IDs that are available for tenant network allocation
vxlan_group = None	(StrOpt) Multicast group for VXLAN. If unset, disables VXLAN multicast mode.