title: Octave: Loaded package is not recognized
body: <p>I have installed package <code>image</code> via <code>pkg install -forge image</code> and after tons of warnings (I am using <em>clang</em> as a C compiler, yeah, I know...) it finished installing.</p>
  
  <p>I then loaded the package with ordinary <code>pkg load image</code> and Octave did not complain. But when I typed <code>help viscircles</code> to get some help on the function, Octave behaved like there was no package <code>image</code>, meaning it returned</p>
  
  <pre><code>&gt;&gt; help viscircles
  error: help: the 'viscircles' function belongs to the image package 
  from Octave Forge but has not yet been implemented.
  
  Please read &lt;http://www.octave.org/missing.html&gt; to learn how you can
  contribute missing functionality.
  </code></pre>
  
  <p>Now I executed the <code>pkg list</code> to see if the package was indeed installed and loaded and yes, it was (there was an asterisk next to <code>image</code> package, which indicates that the certain package is loaded).</p>
  
  <p>I decided to unload all packages and so I did. Now, before loading <code>image</code> again, I executed <code>help viscircles</code> again, but this time I got the next error:</p>
  
  <pre><code>&gt;&gt; help viscircles
  error: help: the 'viscircles' function belongs to the image package 
  from Octave Forge which you have installed but not loaded.  To load the 
  package, run 'pkg load image' from the Octave prompt.
  </code></pre>
  
  <p>Interesting... I loaded the package again and same problem as before. I also downloaded the package manually and reinstalled it, same problems.</p>
  
  <p>And yes, I have Octave 4.0.2, the requirements for image 2.6.2 is version 4.0.0+.</p>