code: function litmus() {
    var awsURL = !!CONFIG && !!CONFIG.aws && !!CONFIG.aws.url ? CONFIG.aws.url : false;
  
    return gulp.src('dist/**/*.html')
      .pipe($.if(!!awsURL, $.replace(/=('|")(\/?assets\/img)/g, "=$1"+ awsURL)))
      .pipe($.litmus(CONFIG.litmus))
      .pipe(gulp.dest('dist'));
  }
docs: Send email to Litmus for testing. If no AWS creds then do not replace img urls.