code: function(url, prev, done) {
          if (url.indexOf('bootstrap/') === 0) {
            var component = url.substr('bootstrap/'.length+1);
            var file = cmsDir+'/src/scss/bootstrap/_'+component+'.scss';
            try {
              var stats = fs.lstatSync(file);
  
              if (stats.isFile()) {
                return { file: file };
              }
            } catch (ex) {
              // file does not exist
            }
          }
  
          return sass.compiler.NULL; // do nothing
        }
docs: this is a hack to have some selective components from bootstrap overriden without copying the whole bootstrap.scss with all its @imports