Divide a number of div in blocks
<pre><code>&lt;div id="WhateverHolder"&gt;

&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;

&lt;/div&gt;
</code></pre>

<p>that i need to have converted into</p>

<pre><code>&lt;div id="WhateverHolder"&gt;

&lt;div class="block"&gt;
&lt;div class="item first"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item last"&gt;&lt;/div&gt;
&lt;/div&gt;

&lt;div class="block"&gt;
&lt;div class="item first"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item"&gt;&lt;/div&gt;
&lt;div class="item last"&gt;&lt;/div&gt;
&lt;/div&gt;

&lt;/div&gt;
</code></pre>

<p>I have looked for a plugin that can do this but to no avail what is the easiest way to do  this in jQuery</p>
