cleanup(DI): clean up visibility decorators

BREAKING CHANGE:
    Replace @Ancestor() with @Host() @SkipSelf()
    Replace @Unbounded() wwith @SkipSelf()
    Replace @Ancestor({self:true}) with @Host()
    Replace @Unbounded({self:true}) with nothing
    Replace new AncestorMetadata() with [new HostMetadata(), new SkipSelfMetadata()]
    Replace new UnboundedMetadata() with new SkipSelfMetadata()
    Replace new Ancestor({self:true}) with new HostMetadata()

modules/angular2/src/forms/directives/ng_control_group.ts

@@ -1,5 +1,5 @@
 import {Directive, LifecycleEvent} from 'angular2/annotations';
-import {Inject, Ancestor, forwardRef, Binding} from 'angular2/di';
+import {Inject, Host, SkipSelf, forwardRef, Binding} from 'angular2/di';
 import {List, ListWrapper} from 'angular2/src/facade/collection';
 import {CONST_EXPR} from 'angular2/src/facade/lang';
 
@@ -57,7 +57,7 @@ const controlGroupBinding =
 })
 export class NgControlGroup extends ControlContainer {
   _parent: ControlContainer;
-  constructor(@Ancestor() _parent: ControlContainer) {
+  constructor(@Host() @SkipSelf() _parent: ControlContainer) {
     super();
     this._parent = _parent;
   }

modules/angular2/src/forms/directives/ng_control_name.ts

@@ -4,7 +4,7 @@ import {List, StringMap} from 'angular2/src/facade/collection';
 
 import {QueryList} from 'angular2/core';
 import {Query, Directive, LifecycleEvent} from 'angular2/annotations';
-import {forwardRef, Ancestor, Binding, Inject} from 'angular2/di';
+import {forwardRef, Host, SkipSelf, Binding, Inject} from 'angular2/di';
 
 import {ControlContainer} from './control_container';
 import {NgControl} from './ng_control';
@@ -88,7 +88,7 @@ export class NgControlName extends NgControl {
   _added = false;
 
   // Scope the query once https://github.com/angular/angular/issues/2603 is fixed
-  constructor(@Ancestor() parent: ControlContainer,
+  constructor(@Host() @SkipSelf() parent: ControlContainer,
               @Query(NgValidator) ngValidators: QueryList<NgValidator>) {
     super();
     this._parent = parent;

modules/angular2/src/forms/directives/ng_form_control.ts

@@ -3,7 +3,7 @@ import {EventEmitter, ObservableWrapper} from 'angular2/src/facade/async';
 
 import {QueryList} from 'angular2/core';
 import {Query, Directive, LifecycleEvent} from 'angular2/annotations';
-import {forwardRef, Ancestor, Binding} from 'angular2/di';
+import {forwardRef, Binding} from 'angular2/di';
 
 import {NgControl} from './ng_control';
 import {Control} from '../model';

modules/angular2/src/forms/directives/ng_model.ts

@@ -3,7 +3,7 @@ import {EventEmitter, ObservableWrapper} from 'angular2/src/facade/async';
 
 import {QueryList} from 'angular2/core';
 import {Query, Directive, LifecycleEvent} from 'angular2/annotations';
-import {forwardRef, Ancestor, Binding} from 'angular2/di';
+import {forwardRef, Binding} from 'angular2/di';
 
 import {NgControl} from './ng_control';
 import {Control} from '../model';