Refactor

Headlines:
* 20% fewer functional lines of code.
* Integrates the Lo-Dash utility library.
* New global data module consolidates AJAX requests and data munging in one place.
* A hop, skip and a jump from moving to a single-page application (and getting rid of the page-specific JS).

All functionality should remain the same, except for the following:
* More robust deep linking. Hash now updates every time the map does.
* Edges are sorted before being drawn so the ones with the largest counts appear on top.
* The legend has been corrected.
* The legend fades in.