Release 0.2.0

• Integration to default repositories of HACS
• Rename vaccum attributes for mower as described :
  Two attributes added. Both are compiled from existing attributes:
  • error code contains NONE if there is no error and the code from last error code if an error is active.
  • status code contains a copy of activity as long as there is no error and a copy of error code if an error
    is active. This corresponds to the state in the old integration of Wijnand.
  • Attribute names changed: last_error_code -> last_error, error_code -> error, status_code -> state
  • Const ATTR_LAST_ERROR_CODE removed, not used any more.
• Bump py-smart-gardena version to fix #29