This is part2. Add support for these objects:
identity.project(v2.0)
identity.role(v2.0)
identity.user(v2.0)
identity.project(v3)
identity.role(v3)
identity.user(v3)
identity.group(v3)
Closes-Bug: #1400597
Change-Id: I270434d657cf4ddc23c3aba2c704d6ef184b0dbc
Currently, only deleting via IDs is possible for groups, projects
and users.
We should have an optional --domain argument that allows for
a name to be specified for the resource. (Since these are all
namespaced by domains).
Change-Id: I18ace3db85a3969f0b97678d432d6f8368baa9cd