Update versions in requirements.txt and remove deprecated feature

[tofu-rocketry]

Update Django and rest framework versions in requirements.txt as current versions listed have security vulnerabilities. Also remote patterns() as that is deprecated in this later version.

[gregcorbett]

related issue #57

[tofu-rocketry]

I couldn't figure out why the unit tests are failing.

[gregcorbett]

I believe the immediate issue is that in between Django 1.6 and 1.11, patterns has been deprecated and removed.

[tofu-rocketry]

Ah, here's the release notes on that: https://docs.djangoproject.com/en/2.2/releases/1.8/#django-conf-urls-patterns

[tofu-rocketry]

They've also deprecated the PaginationSerializer: https://stackoverflow.com/questions/29128225/django-rest-framework-3-1-breaks-pagination-paginationserializer

[tofu-rocketry]

The pagination looks fiddly to fix, so I'm stopping here for the moment. Good news is that the Python 3 build is now failing on the same PaginationSerializer import error!