nicira_role: rename and expand test for any reply
nicira_role: add test for permissions checking
nicira_role: add a test for packet-in
nicira_role: add RoleSwitch test

This test has to be disabled by default because it requires special switch
configuration.
nicira_role: add EqualAsyncMessages test

Requires special switch configuration.
Merge branch 'nicira-role'
nicira_role: add module description