fixes #5334: html snippet comments

docs/javascript.html

@@ -249,10 +249,10 @@ $('#myModal').on('show', function (e) {
             <a data-toggle="modal" href="#myModal" class="btn btn-primary btn-large">Launch demo modal</a>
           </div>
 <pre class="prettyprint linenums">
-&lt;-- Button to trigger modal --&gt;
+&lt!-- Button to trigger modal --&gt;
 &lt;a href="#myModal" role="button" class="btn" data-toggle="modal"&gt;Launch demo modal&lt;/a&gt;
 
-&lt;-- Modal --&gt;
+&lt!-- Modal --&gt;
 &lt;div id="myModal" class="modal hide fade" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true"&gt;
   &lt;div class="modal-header"&gt;
     &lt;button type="button" class="close" data-dismiss="modal" aria-hidden="true"&gt;&times;&lt;/button&gt;

docs/templates/pages/javascript.mustache

@@ -179,10 +179,10 @@ $('#myModal').on('show', function (e) {
             <a data-toggle="modal" href="#myModal" class="btn btn-primary btn-large">{{_i}}Launch demo modal{{/i}}</a>
           </div>{{! /example }}
 <pre class="prettyprint linenums">
-&lt;-- Button to trigger modal --&gt;
+&lt!-- Button to trigger modal --&gt;
 &lt;a href="#myModal" role="button" class="btn" data-toggle="modal"&gt;{{_i}}Launch demo modal{{/i}}&lt;/a&gt;
 
-&lt;-- Modal --&gt;
+&lt!-- Modal --&gt;
 &lt;div id="myModal" class="modal hide fade" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true"&gt;
   &lt;div class="modal-header"&gt;
     &lt;button type="button" class="close" data-dismiss="modal" aria-hidden="true"&gt;&times;&lt;/button&gt;