Remove INTERNAL_IP from global settings, was used twice
Use the new syntax for the URL function for Django 1.5

The "load url from future" is only needed for older versions
Don't use direct_to_template but a class based generic view
Change the regular expression for the URL, doesn't work with Django 1.5
Update the JS for the exercise tabs, JQuery changed the API for tabs widget
Update the Django versions to test against
Pin version of django-browserid, there were some API changes in 0.8
Merge