Split ./spec into unit and support folders
Move unit tests to ./unit folder
Load in files from manifest.js
Update README
Update paths in Gruntfile
Clean up structure and fix loading of scripts

There was no dependancy in the loading of each
script of the previous one having loaded.
Update README to reflect manifest.js move
Merge pull request #122 from alphagov/add-local-specrunner

Add local specrunner