In 'angular2/di' the symbol:
- Inject is a decorator
- InjectAnnotation is an annotation
Internally one an get a hold of annotations without *Annotations appened
(to make ts2dart work without workarounds) by importing from
'angular2/src/di/annotations_impl' instead of 'angular2/di'. This is
needed only for users that transpile through TS and through ts2dart.
Major changes:
- `compiler.compileRoot(el, type)`
-> `compiler.compileInHost(type) + viewHydrator.hydrateHostViewInPlace(el, view)`
- move all `hydrate`/`dehydrate` methods out of `View` and `ViewContainer` into
a standalone class `view_hydrator` as private methods and provide new public
methods dedicated to the individual use cases.
Note: This PR does not change the current functionality, only moves it
into different places.
See design discussion in #1351, in preparation for imperative views.
