Omni-api

Added

* Definition of the `Task` class

Fixed

* Dictionary structure of the payload structures

Changed

* Improved payload values for SAFT-PT API

Added

* Support for `SaftPtAPI` API methods

Changed

* Made code `black` compliant
* Removed extra elements of Python files header

Added

* Support for the `digest_identifier_document()` method
* Support for the `ReceiptAPI`
* Support for issue and ensure receipt operations for `SaleAPI`

Added

* Support for the `get_status` method

Added

* Support for the update self on `SystemCompany`

Changed

* Renamed repository