def read_config_file(file)
      file = File.expand_path(file)
      next_config = safe_load_file(file)
      check_config_is_hash!(next_config, file)
      Jekyll.logger.info "Configuration file:", file
      next_config
    rescue SystemCallError
      if @default_config_file ||= nil
        Jekyll.logger.warn "Configuration file:", "none"
        {}
      else
        Jekyll.logger.error "Fatal:", "The configuration file '#{file}'
          could not be found."
        raise LoadError, "The Configuration file '#{file}' could not be found."
      end
    end
def read_config_file(file)
      file = File.expand_path(file)
      next_config = safe_load_file(file)
      check_config_is_hash!(next_config, file)
      Jekyll.logger.info "Configuration file:", file
      next_config
    rescue SystemCallError
      if @default_config_file ||= nil
        Jekyll.logger.warn "Configuration file:", "none"
        {}
      else
        Jekyll.logger.error "Fatal:", "The configuration file '#{file}'
          could not be found."
        raise LoadError, "The Configuration file '#{file}' could not be found."
      end
    end
Public: Read configuration and return merged Hash

 file - the path to the YAML file to be read in

 Returns this configuration, overridden by the values in the file