Currently downgraded ng2 elements fail inside a ui-router view because they are unable
to require an ng2 Injector via the require attribute of the DDO, because ui-router compiles
its templates before they are inserted in a ui-view. This adds a "fallback" behavior if
a parent injector cannot be found to go to the root ng2 Injector.
Delays NG1 Directive controller instatiation where possible and pre-link function always
to the ngOnInit() lifecycle hook. This way bindings are always available on $scope in both
the controller and the link function.
