code: def load(self, filename=None):
          
          if not filename:
              for name in self.find_default(".pelix.conf"):
                  self.load(name)
          else:
              with open(filename, "r") as filep:
                  self.__parse(json.load(filep))
docs: Loads the given file and adds its content to the current state.
          This method can be called multiple times to merge different files.
  
          If no filename is given, this method loads all default files found.
          It returns False if no default configuration file has been found
  
          :param filename: The file to load
          :return: True if the file has been correctly parsed, False if no file
                   was given and no default file exist
          :raise IOError: Error loading file