Add network segment range command object in support of network segment
range management.

This patch set includes documentation, unit tests and functional tests
(currently skipped unit network segment range enabled in Neutron by
default) for the following new commands:
  - "os network segment range create"
  - "os network segment range delete"
  - "os network segment range list"
  - "os network segment range set"
  - "os network segment range show"

Co-authored-by: Allain Legacy <Allain.legacy@windriver.com>

[depends on removed by dtroyer as those are all +W and 
trying to pass the gate, OSC has it's freeze dealine looming]
 Depends: https://review.openstack.org/624708
 Depends: https://review.openstack.org/624709
 Depends: https://review.openstack.org/638386

Partially-implements: blueprint network-segment-range-management
Change-Id: I335692f2db5be07c1c164f09b13f1abb80b7ba33

With passing "--detail" argument to "openstack quota list", details
about current usage should be returned.
It is currently supported by Nova and Neutron so details of
resources from those projects can be returned.

Change-Id: I48fda15b34283bb7c66ea18ed28262f48b9229fe
Related-Bug: #1716043

Add a parameter ``--floating-ip-address`` to ``floating ip list``
because it's supported by the API and also more efficient than the
current ``floating ip show``. This also works as a work-around for
pagination issues ``floating ip show`` might run into with an IP
parameter.

Change-Id: I113e3fa2495e1e86bb553c55c44f71a3f9f49d23

Adds --qos-policy and --no-qos-policy to `openstack router set`:
    --qos-policy <qos-policy> Attach QoS policy to router gateway IPs
    --no-qos-policy Remove QoS policy from router gateway IPs

Adds --qos-policy to `openstack router unset`:
  --qos-policy Remove QoS policy from router gateway IPs

Partially-Implements blueprint: router-gateway-ip-qos
Closes-Bug: #1757044
Change-Id: Ifec3b2cf9bdb59513c8bcd7bd60305506a071192