Don't break when trying to check if TemplateHooks apply on 404s.

On 404 pages, the request doesn't have a resolver_match. For TemplateHooks
that apply to base.html (like the base-css hook point, for example), this
was problematic because 404.html extends base.html, and so any TemplateHook
that injects itself in a base hook point on only certain pages would cause
breakages since the resolver_match couldn't be checked to see if the
TemplateHook should actually apply.

Reviewed at https://reviews.reviewboard.org/r/6035/.
Speed up the modalbox background fade, and make it darker.

This reduces the time of the modalbox background by more than half,
and makes the background darker. This helps to make things feel faster
when popping up a modalbox, and helps the modalbox to stand out better.

Reviewed at https://reviews.reviewboard.org/r/6149/
Add support for radio actions and label classes in config forms.

This adds the ability to add radio actions to list items in config
forms. These work just like checkboxes, and can be given a name for
grouping.

Labels also have a class name now, so that they can be styled or
referenced. These are named similarly to the actions themselves.

Reviewed at https://reviews.reviewboard.org/r/6157/
Allow items in configform lists to fade in/out when added/removed.

This adds an 'animateItems' option that, if set, will fade in newly
added items and fade out removed items. This can be controlled by the
'animate' option when adding/removing items, and will default to true if
'animateItems' is turned on.

Reviewed at https://reviews.reviewboard.org/r/6151/
Merge branch 'release-0.8.x'