Break turbo mode out of the core framework and make it an extension

[ccampbell]

This is kind of a big undertaking because a lot of the core parts of the app are touched when rendering views/controllers in turbo mode, but it would be a good test for me to see how extendable the framework really is and if I can successfully overwrite the core view/controller stuff.

This may require adding additional delegate methods and delegate files for things other than App.