remove common-table class in the docs

docs/index.html

@@ -512,7 +512,7 @@
         </tbody>
       </table>
 <pre class="prettyprint linenums">
-&lt;table class="common-table"&gt;
+&lt;table&gt;
   ...
 &lt;/table&gt;</pre>
       <h3>Example: Zebra-striped</h3>
@@ -549,7 +549,7 @@
       </table>
       <p><strong>Note:</strong> Zebra-striping is a progressive enhancement not available for older browsers like IE8 and below.</p>
 <pre class="prettyprint linenums">
-&lt;table class="common-table zebra-striped"&gt;
+&lt;table class="zebra-striped"&gt;
 ...
 &lt;/table&gt;</pre>
       <h3>Example: Zebra-striped w/ TableSorter.js</h3>
@@ -591,7 +591,7 @@
     $("table#sortTableExample").tablesorter({ sortList: [[1,0]] });
   });
 &lt;/script&gt;
-&lt;table class="common-table zebra-striped"&gt;
+&lt;table class="zebra-striped"&gt;
   ...
 &lt;/table&gt;</pre>
     </div>