Remove isolated scope #2761

Removing isolated scopes allow us to reduce the count of
'parentValueWatch' required to manage isolated scopes. Our
directives are slightly less re-usable (because dependent on
external scope), but much faster
Fix e2e tests #2761
Avoid extra work of replacing directive #2761

This feature will be dropped in Angular 2.0 and implies more
processing that should not be needed anyway.