Replace make with app #145

We still need insert and remove functions for blocks, so instead of removing Make completely i morphed it into app. It only has 2 methods and stores a reference to the actual app on the model with a `data` property on the app instance.

Not 100% happy with this, suggestions welcome
Log, return, and (eventually) display an error state vs. throw might be a better option as this is not unrecoverable.