This patch does the following things to transfer
"ip floating pool list" to "floating ip pool list":
* Add a new command "floating ip pool list" to deprecate
"ip floating pool list". The source code is in network/v2
dir.
* Add doc for "floating ip pool list".
* Add floating ip pool unit tests.
Change-Id: Id410f4e4a96cf589a6e8def209574da71395b55f
Implements: blueprint rework-ip-commands
Partial-bug: 1555990
Co-Authored-By: Dean Troyer <dtroyer@gmail.com>