title: node-sass installation issue on windows 10
body: <p>I have installed node js latest version(8.8.1) and npm latest version(5.5.1)
  and when i try to install node-sass i get this:</p>
  
  <pre><code>npm install -g node-sass
  </code></pre>
  
  <p>C:\Users\Giannis\AppData\Roaming\npm\node-sass -> C:\Users\Giannis\AppData\Roaming\npm\node_modules\node-sass\bin\node-sass</p>
  
  <blockquote>
    <p>node-sass@4.5.3 install C:\Users\Giannis\AppData\Roaming\npm\node_modules\node-sass
    node scripts/install.js</p>
  </blockquote>
  
  <p>'node' is not recognized as an internal or external command,
  operable program or batch file.
  npm ERR! code ELIFECYCLE
  npm ERR! errno 1
  npm ERR! node-sass@4.5.3 install: <code>node scripts/install.js</code>
  npm ERR! Exit status 1
  npm ERR!
  npm ERR! Failed at the node-sass@4.5.3 install script.
  npm ERR! This is probably not a problem with npm. There is likely additional logging output above.</p>
  
  <p>npm ERR! A complete log of this run can be found in:
  npm ERR!     C:\Users\Giannis\AppData\Roaming\npm-cache_logs\2017-10-26T11_57_10_751Z-debug.log</p>
  
  <p>I have set the system variable
   C:\Program Files\nodejs\</p>
  
  <p>Thanks</p>