title: Transclusion/include in Sphinx static doc generator?
body: <p>I'm writing documentation for a family of products. Some of the sub-sections are identical for some of the different products. I would like to be able to write the text once, and "include" the same text in various pages so I don't interrupt the flow of the reader by having to jump somewhere else and then find their way back.</p>
  
  <p>Bonus points if the included text can take "parameters".</p>
  
  <p>Example document hierarchy and text:</p>
  
  <ul>
  <li><p>How to brush your teeth with an adult toothbrush</p>
  
  <p><code>Go to the a drug store and buy an adult toothbrush.
   #include('common', 'adult toothbrush')
   Brush for 3 minutes.
  </code></p></li>
  <li><p>How to brush your teeth with a kid toothbrush</p>
  
  <p><code>Ask your parent to go to the drug store and buy a kid toothbrush.
   #include('common', 'kid toothbrush')
   Brush until your parent says you are done.
  </code></p></li>
  </ul>
  
  <p>Where common is something like:</p>
  
  <p><code>Put some toothpaste on your $arg1.</code></p>
  
  <p>From what I can tell, this is not built-in functionality. Can it be done with an extension?</p>