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.
Why are you changing the var from machineResponse to createdMachine? It seems like we're only looking at the response (e.g. err) here so it's not actually a more accurate var name.