title: Sonarqube No language plugin error when upgraded from 6.0 to 6.4
body: <p>I upgraded sonarqube from 6.0 to 6.4 on Jenkins</p>
  
  <p>Sonar analysis was working fine with 6.0 but after the upgrade I got an error saying: <strong>No quality profiles have been found, you probably don't have any language plugin installed</strong></p>
  
  <p>What's going wrong here?</p>