Added busterjs test suite for testing server-side code

This commit adds a scaffolding for testing server-side requirejs modules. To
facilitate this I had to move my requirejs config options in web.js out into their
own file (which is good anyway, in the interests of modularity).

TODO: Actually write some tests, like I should have done in the first place!
Added busterjs grunt job
Replaced server-side underscore dep with lodash

I know--ironic, considering the focus of the project...