title: Save UML diagrams in XMI file
body: <p>How I can save my UML <strong>2.5</strong> diagrams in XMI files. I read specifications for UML and XMI but I not enough know English to clearly understand it.
  <br>I very need in example of xmi file that contains some UML 2.5 diagram. But I cannot find so samples. Or some documentation which will be easier than OMG specifications. Are some samples of XMI or docs exist?</p>