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.
This is a totally new function, right, not overwriting anything?