Resolve deprecation warnings with Django 1.8

[dvinegla]

RemovedInDjango19Warning: Loading the url tag from the future library is deprecated and will be removed in Django 1.9. Use the default url tag instead.

base.html
{% load url from future %}

[xordoquy]

This is blocked by the support of Django < 1.5

[tomchristie]

Okay, lets plan to resolve this at the same time as we drop support for 1.4.
I have no issue with us bumping up some versions in our next major release.

[xordoquy]

Agreed.

[foresmac]

Not sure if this was addressed already or not:

/usr/local/lib/python2.7/site-packages/rest_framework/settings.py:23: RemovedInDjango19Warning: django.utils.importlib will be removed in Django 1.9.

[kevin-brown]

Not sure if this was addressed already or not:

That was addressed in #2567.

[foresmac]

@kevin-brown Thanks!