Also acceptance test errors here:
```
Given I have created a LaTeX Problem                                                                # cms/djangoapps/contentstore/features/problem-editor.py:156
Traceback (most recent call last):
  File "/usr/local/Cellar/python/2.7.4/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/lettuce/core.py", line 143, in __call__
    ret = self.function(self.step, *args, **kw)
  File "/Users/db/dev/edx-platform/cms/djangoapps/contentstore/features/problem-editor.py", line 159, in create_latex_problem
    world.css_click('#ui-id-2', success_condition=lambda: world.css_has_class('div.ui-tabs li', 'ui-state-active', index=1))
  File "/Users/db/dev/edx-platform/common/djangoapps/terrain/ui_helpers.py", line 88, in css_click
    world.css_find(css_selector)[index].click()
  File "/usr/local/Cellar/python/2.7.4/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/splinter/driver/webdriver/__init__.py", line 344, in click
    self._element.click()
  File "/usr/local/Cellar/python/2.7.4/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/selenium/webdriver/remote/webelement.py", line 54, in click
    self._execute(Command.CLICK_ELEMENT)
  File "/usr/local/Cellar/python/2.7.4/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/selenium/webdriver/remote/webelement.py", line 228, in _execute
    return self._parent.execute(command, params)
  File "/usr/local/Cellar/python/2.7.4/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 165, in execute
    self.error_handler.check_response(response)
  File "/usr/local/Cellar/python/2.7.4/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/selenium/webdriver/remote/errorhandler.py", line 158, in check_response
    raise exception_class(message, screen, stacktrace)
ElementNotVisibleException: Message: u'element not visible\n  (Session info: chrome=28.0.1500.71)\n  (Driver info: chromedriver=2.1,platform=Mac OS X 10.8.4 x86_64)' 
```