feat(Directive): convert properties to an array

fixes #2013

BREAKING CHANGE:

Before

    @Directive(properties: {
      'sameName': 'sameName',
      'directiveProp': 'elProp | pipe'
    })

After

    @Directive(properties: [
      'sameName',
      'directiveProp: elProp | pipe'
    ])

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

@@ -8,7 +8,7 @@ import {NumberWrapper} from 'angular2/src/facade/lang';
 
 @Component({
   selector: 'md-switch',
-  properties: {'checked': 'checked', 'disabled': 'disabled'},
+  properties: ['checked', 'disabled'],
   hostListeners: {'keydown': 'onKeydown($event)'},
   hostProperties:
       {'checked': 'attr.aria-checked', 'disabled_': 'attr.aria-disabled', 'role': 'attr.role'}