Revert "BLD-1049: Remove Group Configurations."

This reverts commit 27013e74f41c4339cdeb77234a083bfc12d160b9.

That commit appears to be responsible for the cms failures. It is the only commit on master build 2139, where these errors began to appear:
```
Traceback (most recent call last):
  File "/home/jenkins/edx-venv/src/lettuce/lettuce/core.py", line 144, in __call__
    ret = self.function(self.step, *args, **kw)
  File "/home/jenkins/workspace/edx-all-tests-auto-master/SHARD/2/TEST_SUITE/cms-acceptance/cms/djangoapps/contentstore/features/html-editor.py", line 13, in i_created_blank_html_page
    world.create_course_with_unit()
  File "/home/jenkins/workspace/edx-all-tests-auto-master/SHARD/2/TEST_SUITE/cms-acceptance/cms/djangoapps/contentstore/features/common.py", line 265, in create_course_with_unit
    world.css_click(selector)
  File "/home/jenkins/workspace/edx-all-tests-auto-master/SHARD/2/TEST_SUITE/cms-acceptance/common/djangoapps/terrain/ui_helpers.py", line 449, in css_click
    wait_for_js_to_load()
  File "/home/jenkins/workspace/edx-all-tests-auto-master/SHARD/2/TEST_SUITE/cms-acceptance/common/djangoapps/terrain/ui_helpers.py", line 76, in wait_for_js_to_load
    world.wait_for_requirejs(requirements)
  File "/home/jenkins/workspace/edx-all-tests-auto-master/SHARD/2/TEST_SUITE/cms-acceptance/common/djangoapps/terrain/ui_helpers.py", line 190, in wait_for_requirejs
    result = world.browser.driver.execute_async_script(dedent(javascript))
  File "/home/jenkins/edx-venv/local/lib/python2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 415, in execute_async_script
    {'script': script, 'args':converted_args})['value']
  File "/home/jenkins/edx-venv/local/lib/python2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 164, in execute
    self.error_handler.check_response(response)
  File "/home/jenkins/edx-venv/local/lib/python2.7/site-packages/selenium/webdriver/remote/errorhandler.py", line 164, in check_response
    raise exception_class(message, screen, stacktrace)
TimeoutException: Message: u'asynchronous script timeout: result was not received in 60 seconds\n  (Session info: chrome=30.0.1599.114)\n  (Driver info: chromedriver=2.6.232917,platform=Linux 3.2.0-54-virtual x86_64)' 
```