Update a bunch of stuff in the docs.
I just did a read-through of the docs to check for things that are out of date.

Aside from having to completely rewrite the 'post-review' page, and many of our

screenshots being old and out of date, there were a few text changes that

needed to be made:

The reference to "Getting Started" in the codebase "Custom Forks" page wasn't

  correct.
The "Unit Tests Fixtures" page still listed test_reviewrequests and didn't

  have any information about the new TestCase class.
The minimum browser versions still said we supported IE7.
The "What is Code Review" page had out of date information about the state of

  our support for post-commit review.
There was a typo in the paragraph about the "Bugs" field.
There was no documentation for the "Depends On" field.

Built user manual and codebase html and looked at the results.