Added an interface that fragments can use to try to communicate network activity and errors to the Activity. Made the BusinessFormFragment scaffold a user if it isn't already created, use the interface, and marshall its network activity properly.
Factored out the push-to-the-Activity stuff, asynchronised the ConfirmationFragment.
Tested and corrected the new logic that puts the BusinessFormFragment in charge of scaffolding on demand, which meant slightly tweaking the status codes. Added logic to the network fragment to attempt automatically to reset the network activity count if it's non-zero upon activity destruction. Removed scaffolding from the SignupFragment as a test.