title: Homebrew keep showing warning to set PATH on OS X 10.11
body: <p>I am on Mac OSX 10.11 after running</p>
  
  <pre><code>brew doctor
  </code></pre>
  
  <p>And there is a warning in my terminal.</p>
  
  <pre><code>Warning: Homebrew's sbin was not found in your PATH but you have installed
  formulae that put executables in /usr/local/sbin.
  Consider setting the PATH for example like so
  echo 'export PATH="/usr/local/sbin:$PATH"' &gt;&gt; ~/.zshrc
  </code></pre>
  
  <p>After I fixed this PATH in my <code>.zshrc</code> file, I run <code>brew doctor</code> again,
  this error is still remain.</p>
  
  <p>Any suggestions?</p>