title: Assetic: no Ruby script found in input (LoadError)
body: <p>after cloning a symfony2 repo, when I try to compile the assets with php app/console assetic:dump the following error occurs:</p>
  
  <p>[Assetic\Exception\FilterException]<br>
    An error occurred while running:<br>
    '/Users/doe/.rbenv/shims/ruby' '/Users/doe/.rbenv/shims/sass' '--load-path' '/Applications/MAMP/htdocs/myapp/src/AppBundle/Resources/public/sass' '--scss' '--load-path' '/Applications/MAMP/htdocs/myapp/app/../web' '--cache-location' '/Applications/MAMP/htdocs/myapp/app/cache/dev' '/private/var/folders/8y/9vsj9q0d5c5155sj5vgk3<br>
    7p40000gn/T/assetic_sass5LiBb1'<br>
    Error Output:<br>
    ruby: no Ruby script found in input (LoadError)<br>
    Input: [sass file code here]</p>
  
  <p>Could not figure out whats wrong, as path to executables are all OK. Any suggestions?</p>
  
  <p>Thanks!</p>