title: requires a peer of grunt@>=0.4.0
body: <p>Why do I get the error below? My grunt version is > v0.4.0</p>
  
  <pre><code>npm install grunt-contrib-concat --save-dev
  </code></pre>
  
  <blockquote>
    <p>+-- UNMET PEER DEPENDENCY grunt@>=0.4.0</p>
  </blockquote>
  
  <p>Error messages: </p>
  
  <blockquote>
    <p>..Projects\Hartz\Hartz>npm install grunt-contrib-concat --save-dev
    Hartz@1.0.0 C:..\Projects\Hartz\Hartz
    +-- UNMET PEER DEPENDENCY grunt@>=0.4.0 `-- grunt-contrib-concat@1.0.1</p>
    
    <p>npm WARN grunt-contrib-jshint@1.0.0 requires a peer of grunt@>=0.4.0
    but none was installed. npm WARN grunt-contrib-concat@1.0.1 requires a
    peer of grunt@>=0.4.0 but none was installed. npm WARN Hartz@1.0.0 No
    repository field.</p>
  </blockquote>
  
  <p>grunt -V </p>
  
  <blockquote>
    <p>grunt-cli v1.2.0 <br>grunt v1.0.1</p>
  </blockquote>