refactor: rename annotations to metadata

BREAKING CHANGE (maybe)

Well as long as our customers use public API this should not be a
breaking change, but we have changed import structure as well as
internal names, so it could be breaking.

import:
  angular2/annotations => angular2/metadata

Classes:
  *Annotations => *Metadata
  renderer.DirectiveMetadata => renderer.RendererDirectiveMetadata
  renderer.ElementBinder => renderer.RendererElementBinder
  impl.Directive => impl.DirectiveMetadata
  impl.Component => impl.ComponentMetadata
  impl.View => impl.ViewMetadata

Closes #3660

modules/angular2/src/directives/ng_class.ts

@@ -1,5 +1,5 @@
 import {isPresent, isString, StringWrapper, isBlank} from 'angular2/src/facade/lang';
-import {Directive, LifecycleEvent} from 'angular2/annotations';
+import {Directive, LifecycleEvent} from 'angular2/metadata';
 import {ElementRef} from 'angular2/core';
 import {Renderer} from 'angular2/src/render/api';
 import {

modules/angular2/src/directives/ng_for.ts

@@ -1,4 +1,4 @@
-import {Directive, LifecycleEvent} from 'angular2/annotations';
+import {Directive, LifecycleEvent} from 'angular2/metadata';
 import {ViewContainerRef, ViewRef, TemplateRef} from 'angular2/core';
 import {ChangeDetectorRef, IterableDiffer, IterableDiffers} from 'angular2/change_detection';
 import {isPresent, isBlank} from 'angular2/src/facade/lang';

modules/angular2/src/directives/ng_if.ts

@@ -1,4 +1,4 @@
-import {Directive} from 'angular2/annotations';
+import {Directive} from 'angular2/metadata';
 import {ViewContainerRef, TemplateRef} from 'angular2/core';
 import {isBlank} from 'angular2/src/facade/lang';
 

modules/angular2/src/directives/ng_non_bindable.ts

@@ -1,4 +1,4 @@
-import {Directive} from 'angular2/annotations';
+import {Directive} from 'angular2/metadata';
 
 /**
  * The `NgNonBindable` directive tells Angular not to compile or bind the contents of the current

modules/angular2/src/directives/ng_style.ts

@@ -1,4 +1,4 @@
-import {Directive, LifecycleEvent} from 'angular2/annotations';
+import {Directive, LifecycleEvent} from 'angular2/metadata';
 import {ElementRef} from 'angular2/core';
 import {KeyValueDiffer, KeyValueDiffers} from 'angular2/change_detection';
 import {isPresent, isBlank, print} from 'angular2/src/facade/lang';

modules/angular2/src/directives/ng_switch.ts

@@ -1,4 +1,4 @@
-import {Directive} from 'angular2/annotations';
+import {Directive} from 'angular2/metadata';
 import {Host} from 'angular2/di';
 import {ViewContainerRef, TemplateRef} from 'angular2/core';
 import {isPresent, isBlank, normalizeBlank, CONST_EXPR} from 'angular2/src/facade/lang';