Add name arguments to keystone command.

Fixes #Bug 1183655

This patch adds name arguments to the following subcommands:
  * user-list
  * user-create
  * endpoint-create

Change-Id: I056e87de78f88f6fcf76baa4c820622c42f74f39
Sync install_venv_common from oslo

Change-Id: Ic473e2bc51cd55c712aba86af1ffad8252b7b732
Merge "Add name arguments to keystone command."
Merge "Sync install_venv_common from oslo"