Make sure review aggregation task happens once the request is over (bug 995305)

This should ensure that, like indexation tasks, we don't do this too soon,
before the transaction has been committed.
Merge pull request #2674 from diox/dont-call-ratings-task-too-soon

Make sure review aggregation task happens once the request is over (bug 995305)
Display if an app is in China queue in reviewer detail page (bug 1064284)
Update MDN links (bug 1082657)
Bump app-validator
Rename domain to origin in reviewer tools, put it above the fold (bug 1081667)

(Only above the fold for packaged apps, hosted app should stay the same)
Merge pull request #2680 from diox/origin-above-the-fold

Rename domain to origin in reviewer tools, put it above the fold (bug 1081667)
Merge pull request #2677 from diox/developers-mdn-links-update

Update MDN links (bug 1082657)
Add region info to reviewer details (bug 889991)
Merge pull request #2676 from diox/reviewers-display-in-china-queue

Display if an app is in China queue in reviewer detail page (bug 1064284)
Allow clients to select a bigger max-age (bug 1088361)
fix irc channel

No idea where #app-comm came from!
Merge pull request #2678 from diox/client-choose-cache-control-duration

Allow clients to select a bigger max-age (bug 1085739)
Only show FxA migration when the banner is up (bug 1088610)
Use Django's RequestFactory in favor of test_utils.

The test_utils RequestFactory added 'wsgi.input' but Django has been
doing this since 1.4.