fixup AwfulObjectKey, fix busted hash values for ThreadTagKey, UserKey.
Header/import cleanup and formatting.

This was part of a failed attempt to split off the scraping stuff into its own framework. I was trying to figure out a build error "non-modular header inside framework module" and thought combing through headers might be handy. It wasn't, but there's no point wasting the effort.
Fix ScrapingTests for the Model Makeover.

:argh: "Unit tests written in Objective-C cannot import the Swift generated interfaces header ("$(PRODUCT_MODULE_NAME)-Swift.h") for application targets, and therefore cannot be used to test code that requires this header. (16931027)"

Bonus:
* Run the ScrapingTests inside the Awful app once more. We'll sub in a no-op app delegate to avoid pointless launching. This also means ScrapingTests don't need any CocoaPods, so delete that part too. (This is why ScrapingTests now link against Smilies.framework: it's currently where HTMLReader code sits.)
* Fix a couple of bugs from the Model Makeover.
* Move NSURL+QueryDictionary into Scraping folder and group. No point leaving it on its own when it's tested alongside scraping stuff.