New advertising page

Big redesign of the /advertising page.  

[huge screenshot for reference](http://i.imgur.com/DWgyyju.png)

You can safely ignore the first commit, as it is just the commit from this PR that I never got around to pushing out prior to this: https://github.com/reddit/reddit-plugin-about/pull/39.  This also depends on https://github.com/reddit/reddit-public/pull/2347 and https://github.com/reddit/reddit-plugin-gold/pull/31

There are obviously a lot of stylistic changes, but the ones I'm most concerned with are the ones in python, specifically:

* sourcing ad links from a subreddit
* sourcing almost all other text content on the page from a few different wikis

Having spent a larger portion of my time thus far doing design work, my python chops are still rough, so pay extra attention there please.

:eyeglasses: @ajacksified @spladug @umbrae @bsimpson63
There's no point in using translation functions on text that isn't in the code.  Since the text will never be extracted for translation there's no way for there to be a valid translation.

Also, check out what happens if you call `_("")` for a fun bonus!