def include_config(*files)
      include_base = File.dirname(@config_file) if @config_file
      files.each do |file|
        path = File.join(include_base, file) if include_base
        include_file(path || file)
      end
    end
def include_config(*files)
      include_base = File.dirname(@config_file) if @config_file
      files.each do |file|
        path = File.join(include_base, file) if include_base
        include_file(path || file)
      end
    end
Includes config code from one or more files, and evals it in the context of this stack.
 Filenames are relative to the file containing the invocation of this method.