This change allows people to set token expiration dates from the API tokens

config page through a date picker. Consequently, expiration dates can also be

updated through the API. We create a RB.DateInlineEditorView to handle the

UI for the date editing.
This also updates the page to show the invalidated/expired text in

in red so that they stand out against valid tokens.
While running the JS unit tests it was discovered that the

RB.InlineEditorView would not disconnect from a window resize event that

it was handling, which caused problems with other JS tests when running the

full suite. This change adds a RB.InlineEditorView.remove() method to

handle this and disconnect from any events.

Created new unit tests for setting the expiration date via the API

  and ran all tests in reviewboard.webapi.tests.test_api_token.py.
Manually tested the API tokens page, setting various expiration dates and

  making sure they were displayed and saved to the database properly.
Created DateInlineEditorView JS tests and ran all JS tests.
Manually tested resizing my browser that had the new review request page

  open on it and saw that any inline editors that I was using on the page

  would resize accordingly.