fix: flip attr / property bind in directives annotations

Fixes #648

Closes #684

modules/angular2/src/directives/foreach.js

@@ -7,7 +7,7 @@ import {ListWrapper} from 'angular2/src/facade/collection';
 @Viewport({
   selector: '[foreach][in]',
   bind: {
-    'in': 'iterableChanges[]'
+    'iterableChanges[]': 'in'
   }
 })
 export class Foreach  {

modules/angular2/src/directives/if.js

@@ -5,7 +5,7 @@ import {isBlank} from 'angular2/src/facade/lang';
 @Viewport({
   selector: '[if]',
   bind: {
-    'if': 'condition'
+    'condition': 'if'
   }
 })
 export class If {

modules/angular2/src/directives/switch.js

@@ -33,7 +33,7 @@ import {Parent} from 'angular2/src/core/annotations/visibility';
 @Decorator({
   selector: '[switch]',
   bind: {
-    'switch': 'value'
+    'value': 'switch'
   }
 })
 export class Switch {
@@ -144,7 +144,7 @@ export class Switch {
 @Viewport({
   selector: '[switch-when]',
   bind: {
-    'switch-when' : 'when'
+    'when' : 'switch-when'
   }
 })
 export class SwitchWhen {