def []=(key, value)
      entry = find_entry(key)
      @dirty = true
      if entry.nil?
        @entries << [key, value]
      else
        entry[1] = value
      end
    end
def []=(key, value)
      entry = find_entry(key)
      @dirty = true
      if entry.nil?
        @entries << [key, value]
      else
        entry[1] = value
      end
    end
Set the entry 'key=value'. If no entry with the
 given key exists, one is appended to the end of the section