title: Orgmode +INCLUDE not allowing partial inclusion of files
body: <p>As per documentation (<a href="http://orgmode.org/manual/Include-files.html#fnd-1" rel="nofollow noreferrer">http://orgmode.org/manual/Include-files.html#fnd-1</a>) I try to include part of the the file in the following way:</p>
  
  <pre><code>#+INCLUDE: "../experiments.org::*Experiments"
  </code></pre>
  
  <p>When running M-x org-publish-curent-project I get an error message </p>
  
  <pre><code>Cannot include file "(...)/experiments.org::*Experiments"
  </code></pre>
  
  <p>At the same time an external link works perfectly and points to the proper headline:</p>
  
  <pre><code>[[../experiments.org::*Experiments]]
  </code></pre>
  
  <p>My versions:</p>
  
  <ol>
  <li>GNU Emacs 25.2.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.24.30) of 2017-06-27</li>
  <li>Org-mode version 8.2.10</li>
  </ol>
  
  <p>Is it a bug? Should I just submit a bug report?</p>