refactor(material): remove imports from 'angular2/angular2'

Closes #5800

modules/angular2_material/src/components/button/button.ts

@@ -1,4 +1,4 @@
-import {Component, View, ViewEncapsulation, OnChanges} from 'angular2/angular2';
+import {Component, View, ViewEncapsulation, OnChanges} from 'angular2/core';
 
 import {TimerWrapper} from 'angular2/src/facade/async';
 import {isPresent} from 'angular2/src/facade/lang';

modules/angular2_material/src/components/checkbox/checkbox.ts

@@ -1,4 +1,4 @@
-import {Component, View, Attribute, ViewEncapsulation} from 'angular2/angular2';
+import {Component, View, Attribute, ViewEncapsulation} from 'angular2/core';
 import {isPresent} from 'angular2/src/facade/lang';
 import {KeyCodes} from 'angular2_material/src/core/key_codes';
 import {KeyboardEvent} from 'angular2/src/facade/browser';

modules/angular2_material/src/components/grid_list/grid_list.ts

@@ -7,7 +7,7 @@ import {
   OnChanges,
   OnDestroy,
   AfterContentChecked
-} from 'angular2/angular2';
+} from 'angular2/core';
 
 import {ListWrapper} from 'angular2/src/facade/collection';
 import {StringWrapper, isPresent, isString, NumberWrapper} from 'angular2/src/facade/lang';

modules/angular2_material/src/components/input/input.ts

@@ -1,4 +1,4 @@
-import {Directive, Attribute, Host, SkipSelf, AfterContentChecked} from 'angular2/angular2';
+import {Directive, Attribute, Host, SkipSelf, AfterContentChecked} from 'angular2/core';
 
 import {ObservableWrapper, EventEmitter} from 'angular2/src/facade/async';
 

modules/angular2_material/src/components/progress-circular/progress_circular.ts

@@ -1,7 +1,7 @@
-import {Component, View, ViewEncapsulation} from 'angular2/angular2';
+import {Component, ViewEncapsulation} from 'angular2/core';
 
-@Component({selector: 'md-progress-circular'})
+@Component({
-@View({
+  selector: 'md-progress-circular',
   templateUrl: 'package:angular2_material/src/components/progress-circular/progress_circular.html',
   encapsulation: ViewEncapsulation.None
 })

modules/angular2_material/src/components/progress-linear/progress_linear.ts

@@ -1,4 +1,4 @@
-import {Component, View, ViewEncapsulation, Attribute, OnChanges} from 'angular2/angular2';
+import {Component, ViewEncapsulation, Attribute, OnChanges} from 'angular2/core';
 import {CONST} from 'angular2/src/facade/lang';
 import {isPresent, isBlank} from 'angular2/src/facade/lang';
 import {Math} from 'angular2/src/facade/math';
@@ -20,9 +20,7 @@ class ProgressMode {
     'aria-valuemin': '0',
     'aria-valuemax': '100',
     '[attr.aria-valuenow]': 'value'
-  }
+  },
-})
-@View({
   templateUrl: 'package:angular2_material/src/components/progress-linear/progress_linear.html',
   directives: [],
   encapsulation: ViewEncapsulation.None

modules/angular2_material/src/components/radio/radio_button.ts

@@ -1,6 +1,5 @@
 import {
   Component,
-  View,
   ViewEncapsulation,
   Host,
   SkipSelf,
@@ -8,7 +7,7 @@ import {
   Optional,
   OnChanges,
   OnInit
-} from 'angular2/angular2';
+} from 'angular2/core';
 
 import {isPresent, StringWrapper, NumberWrapper} from 'angular2/src/facade/lang';
 import {ObservableWrapper, EventEmitter} from 'angular2/src/facade/async';
@@ -42,9 +41,7 @@ var _uniqueIdCounter: number = 0;
     // TODO(jelbourn): Remove ^ when event retargeting is fixed.
     '(keydown)': 'onKeydown($event)',
     '[tabindex]': 'tabindex',
-  }
+  },
-})
-@View({
   templateUrl: 'package:angular2_material/src/components/radio/radio_group.html',
   encapsulation: ViewEncapsulation.None
 })
@@ -198,9 +195,7 @@ export class MdRadioGroup implements OnChanges {
     '[attr.aria-checked]': 'checked',
     '[attr.aria-disabled]': 'disabled',
     '(keydown)': 'onKeydown($event)',
-  }
+  },
-})
-@View({
   templateUrl: 'package:angular2_material/src/components/radio/radio_button.html',
   directives: [],
   encapsulation: ViewEncapsulation.None

modules/angular2_material/src/components/radio/radio_dispatcher.ts

@@ -1,4 +1,4 @@
-import {Injectable} from 'angular2/angular2';
+import {Injectable} from 'angular2/core';
 
 /**
  * Class for radio buttons to coordinate unique selection based on name.

modules/angular2_material/src/components/switcher/switch.ts

@@ -1,4 +1,4 @@
-import {Component, View, ViewEncapsulation, Attribute} from 'angular2/angular2';
+import {Component, ViewEncapsulation, Attribute} from 'angular2/core';
 import {MdCheckbox} from "../checkbox/checkbox";
 
 // TODO(jelbourn): add gesture support
@@ -12,9 +12,7 @@ import {MdCheckbox} from "../checkbox/checkbox";
     '[attr.aria-checked]': 'checked',
     '[attr.aria-disabled]': 'disabled_',
     '(keydown)': 'onKeydown($event)',
-  }
+  },
-})
-@View({
   templateUrl: 'package:angular2_material/src/components/switcher/switch.html',
   directives: [],
   encapsulation: ViewEncapsulation.None