title: How to combine two models in one RoR acts_as_tree treeview?
body: <p>I have two simple models each with acts_as_tree, say Departments and Employees.
  My goal is to create a treeview combining both models in to one overall tree, like so:</p>
  
  <ul>
  <li>Department 1
  
  <ul>
  <li>SubDepartment 1.1
  
  <ul>
  <li>Employee A  </li>
  <li>Employee B</li>
  </ul></li>
  <li>SubDepartment 1.2  </li>
  </ul></li>
  <li>Department 2  
  
  <ul>
  <li>Subdepartment 2.1
  
  <ul>
  <li>Employee C</li>
  </ul></li>
  </ul></li>
  <li>Department 3
  
  <ul>
  <li>SubDepartment 3.1
  
  <ul>
  <li>Employee D</li>
  <li>Employee E</li>
  </ul></li>
  <li>Subdepartment 3.2  </li>
  </ul></li>
  </ul>
  
  <p>etc</p>
  
  <p>I found this already: <a href="https://stackoverflow.com/questions/2142285/acts-as-tree-with-multiple-models">Acts as Tree with Multiple Models</a> but I'm afraid I could use a little more pointers in the right direction.</p>
  
  <p>Thanks!</p>