feat(Directive): Have a single Directive.host which mimics HTML

fixes #2268

BREAKING CHANGE:

Before

    @Directive({
      hostListeners: {'event': 'statement'},
      hostProperties: {'expression': 'hostProp'},
      hostAttributes: {'attr': 'value'},
      hostActions: {'action': 'statement'}
    })

After

    @Directive({
      host: {
        '(event)': 'statement',
        '[hostProp]': 'expression'  // k & v swapped
        'attr': 'value',
        '@action': 'statement'
      }
    })

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

@@ -218,14 +218,14 @@ export class MdGridList {
 @Component({
   selector: 'md-grid-tile',
   properties: ['rowspan', 'colspan'],
-  hostProperties: {
-    'styleHeight': 'style.height',
-    'styleWidth': 'style.width',
-    'styleTop': 'style.top',
-    'styleLeft': 'style.left',
-    'styleMarginTop': 'style.marginTop',
-    'stylePaddingTop': 'style.paddingTop',
-    'role': 'role'
+  host: {
+    '[style.height]': 'styleHeight',
+    '[style.width]': 'styleWidth',
+    '[style.top]': 'styleTop',
+    '[style.left]': 'styleLeft',
+    '[style.marginTop]': 'styleMarginTop',
+    '[style.paddingTop]': 'stylePaddingTop',
+    '[role]': 'role'
   },
   lifecycle: [onDestroy, onChange]
 })