Weighted scores now working in the refactor and show up correctly on the profile graph. Dropped score markers are back too.

Refactoring grades. Adding more generic grading classes. Probably broken right now. Just committing to save progress.

Added grades SectionPercentage namedtuple. Fixed bug where problem ids were being used for section labels in graph.

Use the base package name as the provided value, rather than the path, because .deb packages can't start with /

Added some styles to make videos more cohesive

Name and e-mail change functionality

Conflicts:
	static/css/application.css
	static/css/marketing.css

Complex numbers now work in problems

* Parallel and exponentials in calc were broken because of this. Confirmed working
* Added test cases for the above
* Fixed a broken test case

Moved site, is_secure, etc. into render_to_string shortcut, and fixed bugs in the shortcut. We should test this pretty well, since this touches a lot of templates