title: size of boost uuid in string returns 36
body: <p>I am trying to generate 16 character uuid string using boost::uuid but it returns 36 characters.</p>
  
  <pre><code>boost::uuids::uuid uid == boost::random_generator()();
  std::cout &lt;&lt; size of uid:" &lt;&lt; uid.size &lt;&lt; std::endl; //always 16
  std::stringstream ss;
  ss&lt;&lt; uid;
  std::string s = ss.str();
  std::cout &lt;&lt; "size of uid:" &lt;&lt; s.size() &lt;&lt; std::endl; // always 36
  </code></pre>
  
  <p>How do I get 16 character uuid string?</p>