- test/models/user_test.rb specifies that a user can now be
  'acting_on_behalf_of' another user
- app/model/user.rb passes this test

- test/models/repository_user.rb specifies that if an admin user is
  acting_on_behalf_of another admin user, they cannot edit, update,
  or destroy the user they are acting_on_behalf_of
- added another admin to test/fixtures/users.yml
- added debug information about user acting_on_behalf_of
  another user in the test/test_helper.rb denied_abilities
  and allowed_abilities
- app/models/ability.rb passes this test

- test/controllers/switch_user_controller_test.rb specifies that
  the current_user.acting_on_behalf_of is set to the id of the
  user that switched to the current_user.  It specifies that
  current_user.acting_on_behalf_of is nil after destroy
- app/controllers/application_controller.rb passes this test

ALL TESTS PASS
Merge branch 'master' of git_data_authority:DataAuthority/rads