docs(ngCloak): remove information for ie7

IE7 is not supported. Also change `#template2` text to `'world'`.

Closes angular#11661

Author: stevemao

src/ng/directive/ngCloak.js

@@ -33,17 +33,13 @@
  * document; alternatively, the css rule above must be included in the external stylesheet of the
  * application.
  *
- * Legacy browsers, like IE7, do not provide attribute selector support (added in CSS 2.1) so they
- * cannot match the `[ng\:cloak]` selector. To work around this limitation, you must add the css
- * class `ng-cloak` in addition to the `ngCloak` directive as shown in the example below.
- *
  * @element ANY
  *
  * @example
    <example>
      <file name="index.html">
         <div id="template1" ng-cloak>{{ 'hello' }}</div>
-        <div id="template2" ng-cloak class="ng-cloak">{{ 'hello IE7' }}</div>
+        <div id="template2" class="ng-cloak">{{ 'world' }}</div>
      </file>
      <file name="protractor.js" type="protractor">
        it('should remove the template directive and css class', function() {