Partial pick: Fix a critical bug which set a unit state value as a store state

Pick note: Didn't pick a comment for a method that we don't have.

Conflicts:
	pootle/apps/pootle_store/models.py
Fixed small visual inconsistency
Fixed footer content's vertical alignment
Fix checks display in various scenarios
Fix body height in order to don't hide the editor overlay
All languages / all projects no longer redirects to the home page

Fixes evernote/pootle#69.
Invalidate qualitycheck count cache value after correction of all errors
Cleanup: minor styling nit
Cleanup: use more explicit function names
Allow sidebar content scrolling
Avoid scrollbar when it's not necessary
Removed copy of json2.js

JSON parsing facilities are built-in in modern browsers.
Patched third-party libraries to remove `$.browser` calls

This is deprecated in newer jQuery versions and we need to get rid of them
to make the switch.
Upgrade jQuery and tipsy

Since tipsy depends on a newer jQuery, committing everything in a single
commit.

Note that to remove dangling tooltips, the `$.fn.tipsy.revalidate()`
function is called in a timely fashion.

Fixes evernote/pootle#63 and fixes evernote/pootle#25.