This patch does the following things to transfer
"ip floating xxx" to "floating ip xxx":
* Add new command "floating ip create/delete/list/show", and doc.
* Deprecate "ip floating create/delete/list/show" command.
Change-Id: Ib071acaac81988431244e858bddafa7f93403df5
Implements: blueprint rework-ip-commands
Closes-bug: 1555990
Co-Authored-By: Dean Troyer <dtroyer@gmail.com>