code: function(className, options) {
    if (!(this instanceof Logger)) return new Logger(className, options);
    options = options || {};
  
    // Current reference
    this.className = className;
  
    // Current logger
    if (currentLogger == null && options.logger) {
      currentLogger = options.logger;
    } else if (currentLogger == null) {
      currentLogger = console.log;
    }
  
    // Set level of logging, default is error
    if (level == null) {
      level = options.loggerLevel || 'error';
    }
  
    // Add all class names
    if (filteredClasses[this.className] == null) classFilters[this.className] = true;
  }
docs: Creates a new Logger instance
  @class
  @param {string} className The Class name associated with the logging instance
  @param {object} [options=null] Optional settings.
  @param {Function} [options.logger=null] Custom logger function;
  @param {string} [options.loggerLevel=error] Override default global log level.
  @return {Logger} a Logger instance.