Test that non-zero exit codes return a nil configuration.
Extract boilerplate for setting up the git task termination handler.
Extract mock data for clarity.
Add error parameter to repository completion handler so we can specify reasons for failure.
Test that delegate is given a “missing configuration” error when the configuration cannot be read.
Test that delegate is given “bad exit code” error when git tool has non-zero termination status.
Use file reader to read data so we can properly stub out the methods without using class methods.
Merge branch 'master' of github.com:dcutting/filament

Conflicts:
	Filament/FLTAppDelegate.m
Reset gitURL and branchName.
FLTFileReader just wraps NSData file reader method so we can stub its functionality in tests.