Restyled Search Results & Crop pages

## Redesign/styling of search results and crop pages (Whoo!)

**Some quick points**
* nav is now fixed (but still broken… har har)
* we're ready for compatibility scores (in the range of 0-100)
* search results and crop pages use a split screen approach where both sides can be scrolled independently
* Crops without images degrade to font awesome leaf
* These are really lame points.

**Things to still do**
* internationalize strings/pluralization
* add back button to crop page (if coming from search)
* make search terms persist in top search bar

Could definitely use some help from @simonv3 and @rickcarlino to look over my Rails code, I have high suspicions I don't have the best of practices. Let me know what ya'll think! (cc @roryaronson, @emily-plummer)

![screen shot 2014-11-14 at 4 23 00 pm](https://cloud.githubusercontent.com/assets/220240/5055586/bbf2aa9e-6c1a-11e4-80cd-db6e9a4a11b2.png)
![screen shot 2014-11-14 at 4 24 50 pm](https://cloud.githubusercontent.com/assets/220240/5055610/0afe99cc-6c1b-11e4-9818-7529fda8c682.png)
This is undoubtedly a model method.

Make a model method in `guide` called `compatibility_score` that does all of these calculations (or returns `nil`) and then just and call `@guide.compatibility_score`.

Also- just now I noticed you were using[:square_brackets] on a model on some commented out code. Let me know if you need help adding a new field. I would prefer to avoid dynamic attributes if we can just because it will be hard for new devs to know what our data looks like ahead of time.