This includes some significant cleanups to the new course categories
system. The basic idea is that the categories/course browser is now
unified under one system, and admin features related to that have
all been moved into the browser (as little icons).
I'm much happier with this as a foundation that can scale and be
built upon.
Still to go:
- searching
- paging
- polishing
Also in here are a lot of little cleanups around the place, such as
the initial setup process.
Sections covers "weeks", "topics" and anything else that may come along.
Note, again, some databases have changed esp course_weeks -> course_sections
and several fields called "week" are now "section. Also course no longer
has an enddate, but instead has a numsections field.
