Updates the handling of the create machine callback handlers to update the existing model instead of destroying and re-creating

Destroying and re-creating the machine model caused the tokens to disappear then re-appear when the deltas came in. Updating the models instead keeps them in the DOM.

Created a new module called 'yui-patches' as a place to put monkey patches to the YUI codebase.
Totally new, correct.

The argument was that I didn't want to have to go and change everywhere in the app which uses it and then re-test the entire app :) This way anyone using LML will just get that functionality. Maybe if we end up adding more than a single method it'll make sense to do that, but atm I think it would be overkill.