title: Disable editing between specified tags in CkEditor
body: <p>As ur experience, there are any way to do that?
  For example, i have a default layout, which loads when the user starts editing an empty document, something like this:</p>
  
  <pre><code>&lt;h1&gt;Sample heading&lt;/h1&gt;
  &lt;p&gt;Sample text&lt;/p&gt;
  &lt;div class="something"&gt;&lt;/div&gt;
  </code></pre>
  
  <p>Here, i want to have a control to prevent ppl starting to writing into the .something div. 
  If possible, i want to disable the possibility to remove my predefined tags too.</p>
  
  <p>Sorry for english, and thanks for the answers! :)</p>