code: public static SystemMain getInstance(Properties config) {
          return Guice.createInjector(new SystemInitializer(config)).getInstance(SystemMain.class);
      }
docs: Returns an instance of the system. Configuration is read from the supplied properties file.
  
  @param config If null, configuration is read from the default location.
  
  @return An instance of the system.
  
  @see SystemConfiguration