Specification to lay out new commands to be added to OSC.
New feature has been implemented and released for Neutron
and python-neutronclient to display IP usages.
Commands will display the IP usage across all networks, or
detailed IP usage specifics for a given network
Partially Implements Blueprint: neutron-ip-capacity
Change-Id: I1c25de1bd924d92a96c20d60fa24d9e966b92dcd
dc3d3ea77b