callbacks for pin and unpin
graceful degradation fix #7
pass window and document to iife for better minification
small tweaks for further minification improvements
make watch default grunt command

I figure you spend more time developing than you do pushing code, so make dev setup the default
swap jasmine runner for karma
travis CI integration fix #13
permit lax breaks in jshint
small tweaks of code style
exit from plugins if jQuery/angular not present
test availability of features object before inspecting
refactor update logic for greater readbility
use dots for karma reporting
ensure tests are independent of one another

order of source and test files being loaded should not be important. ensure this is always the case by using globbing source and test files
return `this` from init()

allows usage as: `var hr = new Headroom(element).init();`
initialise `lastKnownScrollY` to non-zero value when needed
improve logic around when to pin/unpin
correctly expose headroom to global scope
test and readability improvements
cache rAF callback