Add Django 1.11 Support

[rgg-lle]

This pull request adds support for Django 1.11.

Main features:

• the version of Django has been updated to include Django 1.11
• a tox configuration that now runs tests against Django1.11.

To test:

• set up this project locally, and run all tests with tox.
• run the ruetech repo locally
• install the django_1_11 branch of haystack in each of the containers that uses it (cobra-storefront, rue-storemanager, and rue-storefront) by changing each apps’s setup.py file to install savory-pie from GitHub: change 'django-haystack-rgg-fork==2.5.1’, to 'django-haystack @ git+https://yourusername:[email protected]/RueLaLa/django-haystack.git@django_1_11' (fill in your username and GitHub access token) in the following files:
  • src/rue-storemanager/setup.py
  • src/rue-synchronizer/setup.py
• rebuild the Docker containers
• make sure that the site still runs as before
• run all of the tests, and make sure that they all pass, and don’t have any Django1.11 warnings for savory pie