Document error handling

[ebryn]

Our belief is that error handling should be done inside controllers off the returned promises.

[narkeeso]

I am currently using Em.RSVP.on('error') to capture promise errors from Ember model that are not explicitly declared in my app. There is currently no error handler in Ember Model that I am aware of and was wondering if this was the current best way to capture errors?

I also capture errors in ApplicationRoute when the model call is made in routes.