13.1.0: UUID support

• Merged #49: Add support for util.UUID instances (in %s tokens)
  (@thekid)
• Fixed #50: TypeError (get_resource_type(): Argument #1 ($resource)
  must be of type resource, SQLite3 given)
  (@thekid)
• Fixed #51: Warning: Return type of rdbms\ResultSet::getIterator()
  (@thekid)