refactor(views): split ViewManager/ViewContainerRef.createView into 2 methods

BREAKING CHANGES:

`ViewManager.createView` / `ViewContainerRef.create` have been split into 2 methods:

- `createHostView` which takes dynamically created bindings
- `createEmbeddedView` which takes the newly introduced `TemplateRef`

The new type `TemplateRef` is the combination of a `ProtoViewRef` and and `ElementRef`
from the same place. Use `TemplateRef` when working with embedded views in
`ng-if`, `ng-for`, ... instead of `ProtoViewRef`.

Also, `ProtoViewRef` is no more injectable, but `TemplateRef` is.

First part of #1989 to clean up manual content projection.
Closes #3114

modules/angular2/src/core/compiler/compiler.ts

@@ -146,8 +146,8 @@ export class Compiler {
                 return this._compileNestedProtoViews(hostRenderPv, protoView, componentType);
               });
     }
-    return hostPvPromise.then(hostAppProtoView => this._mergeCyclicEmbeddedProtoViews().then(
-                                  _ => new ProtoViewRef(hostAppProtoView)));
+    return hostPvPromise.then(
+        hostAppProtoView => this._mergeCyclicEmbeddedProtoViews().then(_ => hostAppProtoView.ref));
   }
 
   private _compile(componentBinding: DirectiveBinding): Promise<AppProtoView>| AppProtoView {