AMD compatibility & manual initialization

Hi

I have added some changes in my custom branch to support AMD loaders and to be able to initialize Unison "manually". The problem with the original implementation was, that if included it inside your own ```DOMContentLoaded``` listener, the event inside Unison never fires (since it fires once). I added the public ```util.initializeUnison``` method which can be called manually and initializes Unison.

Also, I added an ```.editorconfig``` file to support your syntax and made some format changes. Feel free to include this in your version.