code: function (prefix, preout, messages) {
          if (prefix && this.LEVELS[prefix] < this.level) {
              return;
          }
  
          var msg = "";
          for (var i = 0; i < messages.length; i++) {
              0 < i ? msg += ' ' + messages[i]: msg += messages[i];
          }
          var out = msg;
          if (prefix) { out = preout + ' ' + msg; }
          console.log(out);
      }
docs: colors setup flag 
  @name output
  @memberof logger
  @method
  @param {String} prefix message prefix.
  @param {Array} messages output messages
  @private