title: boost property tree, iterators to an element for inserting?
body: <p>I've searched a lot through the boost manual, and the internet, as I believe it is quite a standard feature?</p>
  
  <p>Well I'm looking into "merging" property trees. - I noticed the function <code>insert</code>, and I hope I can merge trees with this?
  Below is the line which I am trying to get working:</p>
  
  <pre><code>base.insert(base.get_child("BRANCH"), t);
  </code></pre>
  
  <p><code>base</code> and <code>t</code> are "property trees", <code>base</code> has as (one of many) branch "BRANCH". Now I wish to insert <code>t</code> into this branch?<br>
  More specifically: how can I get an iterator to "element" if I know that element by name?</p>