title: Dia add existing class to package
body: <p>I'm using the <a href="https://wiki.gnome.org/Apps/Dia" rel="noreferrer">Dia</a> diagram editor to create an UML for a project, and I want to add a class into a package. This can be easily done when the class is created, then the class and the package are bound and the class can't be moved outside the package.<br>
  But I have designed many of my classes outside of a package and nom I want to add them in a package, and I can't figure out how to add a pre-existing class to a package.</p>
  
  <p>Am I missing something ? Any ideas ?</p>