text: Title: [BUG] 'Settings' object has no attribute 'LANGUAGE_COOKIE_HTTPONLY' with django-cms 3.10 and django 2.2
  Body: <!--
  Please fill in each section below, otherwise, your issue will be closed.
  This info allows django CMS maintainers to diagnose (and fix!) your issue
  as quickly as possible.
  -->
  
  ## Description
  
  Django-CMS 3.10 expects a LANGUAGE_COOKIE_HTTPONLY setting. [This setting is not part of Django in Django 2.2](https://docs.djangoproject.com/en/2.2/ref/settings/) but was [added in Django 3.0](https://docs.djangoproject.com/en/3.0/ref/settings/#language-cookie-httponly).
  
  ## Steps to reproduce
  
  1. Install Django-CMS 3.10 with Django 2.2 LTS.
  
  ## Expected behaviour
  
  Django-CMS should have a fallback value if LANGUAGE_COOKIE_HTTPONLY is missing.
  
  ## Actual behaviour
  
  Django-CMS 3.10 expects the LANGUAGE_COOKIE_HTTPONLY setting, which is not part of Django 2.2, leading to an Internal Server Error.
  
  ## Screenshots
  
  <!--If applicable, add screenshots to help explain your problem.
  -->
  
  ## Additional information (CMS/Python/Django versions)
  
  Django-CMS 3.10
  Django 2.2 LTS
  Python 3.8.x
  
  ```Traceback:
  
  File "/usr/local/envs/[are.ucdavis.edu](http://are.ucdavis.edu/)-3.8/lib64/python3.8/site-packages/django/core/handlers/exception.py" in inner
   34.             response = get_response(request)
  
  File "/usr/local/envs/[are.ucdavis.edu](http://are.ucdavis.edu/)-3.8/lib64/python3.8/site-packages/django/utils/deprecation.py" in __call__
   96.             response = self.process_response(request, response)
  
  File "/usr/local/envs/[are.ucdavis.edu](http://are.ucdavis.edu/)-3.8/lib64/python3.8/site-packages/cms/middleware/language.py" in process_response
   26.             httponly=settings.LANGUAGE_COOKIE_HTTPONLY,
  
  File "/usr/local/envs/[are.ucdavis.edu](http://are.ucdavis.edu/)-3.8/lib64/python3.8/site-packages/django/conf/__init__.py" in __getattr__
   80.         val = getattr(self._wrapped, name)
  
  Exception Type: AttributeError at /
  Exception Value: 'Settings' object has no attribute 'LANGUAGE_COOKIE_HTTPONLY'
  Request information:
  USER: AnonymousUser
  
  GET: No GET data
  
  POST: No POST data
  
  FILES: No FILES data
  ```
  
  <!--
  Add any other context about the problem such as environment,
  CMS/Python/Django versions, logs etc. here.
  -->
  
  ## Do you want to help fix this issue?
  
  <!-- 
  The django CMS project is managed and kept alive by its open source community and is backed by the [django CMS Association](https://www.django-cms.org/en/about-us/). We therefore welcome any help and are grateful if people contribute to the project. Please use 'x' to check the items below.
  -->
  
  * [ ] Yes, I want to help fix this issue and I will join #workgroup-pr-review on [Slack](https://www.django-cms.org/slack) to confirm with the community that a PR is welcome. 
  * [X] No, I only want to report the issue.
  