`user role list` command should be worked into `role list`

[Steve Martinelli]

more info here: https://etherpad.openstack.org/p/user-role-and-roles

basically, v2's `user role list` does the same thing as v3's `role list` but with optional parameters.

v2's `role list` is very under-used, and just gets all roles, we could add new optional parameters to it, and make it more like v3's command, and thus eliminating `user role list`

With v2.0 API
steve:devstack$ openstack user role list demo --project demo
+----------------------------------+-------------+---------+------+
| ID | Name | Project | User |
+----------------------------------+-------------+---------+------+
| 9fe2ff9ee4384b1894a90878d3e92bab | _member_ | demo | demo |
| c8c3b6a623774d95bfe823e08e49a30a | anotherrole | demo | demo |
| 5b3d0bd434af46efa0b285755eae0d06 | Member | demo | demo |
+----------------------------------+-------------+---------+------+

With v3 API
steve:python-openstackclient$ openstack role list --user demo --project demo
+----------------------------------+-------------+---------+------+
| ID | Name | Project | User |
+----------------------------------+-------------+---------+------+
| 5b3d0bd434af46efa0b285755eae0d06 | Member | demo | demo |
| 9fe2ff9ee4384b1894a90878d3e92bab | _member_ | demo | demo |
| c8c3b6a623774d95bfe823e08e49a30a | anotherrole | demo | demo |
+----------------------------------+-------------+---------+------+

[Steve Martinelli (stevemar)]

possible fix here: https://review.openstack.org/#/c/146241/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/146241
Committed: https://git.openstack.org/cgit/openstack/python-openstackclient/commit/?id=ffb783215986318aded3eef0d97b603062f7c7ee
Submitter: Jenkins
Branch: master

commit ffb783215986318aded3eef0d97b603062f7c7ee
Author: Steve Martinelli <email address hidden>
Date: Fri Jan 9 19:58:17 2015 -0500

    Rework role list v2 for --user and --project

    `os user role list` does the same as v3's `os role list`.
    We should rework v2's `role list` to basically call `os user role list`
    under the covers.

    Closes-Bug: #1409179
    Change-Id: I9839f6be139d6a6a3f6bbf79957e218dd8e03fe3