Stretch contents/sidebar up to the max height
Avoid polluting the global namespace
Partial pick: Cleanup: removed dead code

Pick notes: Not picking the changes in templates/ and static/ because
    those are reverted and then added again in a further commit, so
    decided to just don't pick those changes here and pick the last
    commit. The other removal is not necessary.

Conflicts:
	pootle/apps/pootle_translationproject/models.py
Display current project's files/dirs in a third drop-down

Some redirects might be incomplete but they'll be part of evernote/pootle#75.

Fixes evernote/pootle#74.

Pick notes: Had to fix conflicts due to code divergence, but didn't
    alter any of the changes.

Conflicts:
	pootle/apps/pootle_project/models.py
	pootle/core/url_helpers.py
	pootle/static/css/style.css
	pootle/templates/browser/overview.html
Moved navigation-related code into its own file
Refactored common code
Forgot to add the script reference in the js bundle in 953fa23111