Initial refactor.
 - Return home early
 - Extract repeated animator branching logic into internal service
Refactoring 'registerState()' into 'stateBuilder'.
 - Adding tests
 - Adding comments
'data' property inheritance/override in chain of states
Refactoring 'registerState()' into 'stateBuilder'.
 - Adding tests
 - Adding comments
Additional state builder refactoring.
First pass to extract $view into separate service.
Methods for $state now have proper names.
Implementing $state.go(), for relative transitions & param inheritance.
Refactoring 3rd param in $state.transitionTo() to options hash.
Refactoring $state.go() functionality into transitionTo() as options.
Using refactored URL matcher detection in $state, fixes #154
 - Refactoring $urlRouterProvider.when() for improved composability
 - Adding tests for $urlRouterProvider
Final implementation of relative state targeting.