docs(directives): correct property binding examples

Closes angular#2663

Author: pkozlowski-opensource

modules/angular2/src/directives/ng_for.ts

@@ -37,7 +37,7 @@ import {isPresent, isBlank} from 'angular2/src/facade/lang';
  *
  * - `<li *ng-for="#item of items; #i = index">...</li>`
  * - `<li template="ng-for #item of items; #i = index">...</li>`
- * - `<template [ng-for] #item [ng-for-of]="items" #i="index"><li>...</li></template>`
+ * - `<template ng-for #item [ng-for-of]="items" #i="index"><li>...</li></template>`
  *
  * @exportedAs angular2/directives
  */

modules/angular2/src/directives/ng_switch.ts

@@ -38,7 +38,7 @@ export class SwitchView {
  * <ANY [ng-switch]="expression">
  * <template [ng-switch-when]="whenExpression1">...</template>
  * <template [ng-switch-when]="whenExpression1">...</template>
- * <template [ng-switch-default]>...</template>
+ * <template ng-switch-default>...</template>
  * </ANY>
  * ```
  *
@@ -148,7 +148,7 @@ export class NgSwitch {
  * <template [ng-switch-when]="contextVariable">...</template>
  *
  * // match against a constant string
- * <template [ng-switch-when]="'stringValue'">...</template>
+ * <template ng-switch-when="stringValue">...</template>
  * ```
  *
  * @exportedAs angular2/directives
@@ -184,7 +184,7 @@ export class NgSwitchWhen {
  * Example:
  *
  * ```
- * <template [ng-switch-default]>...</template>
+ * <template ng-switch-default>...</template>
  * ```
  *
  * @exportedAs angular2/directives