title: phpstorm, create custom UML diagram
body: <p>PhpStorm has a feature to create UML diagrams based on existing classes</p>
  
  <p>But I need to create and save my own diagrams, that will have objects for not existing classes. For example, I need to create a database diagram and a UML diagram for some classes of new feature.</p>
  
  <p>Can I do it via phpstorm?</p>