Added support for BMW Cardata via MQTT

What's Changed

• force turn charging off, if it was not started by this service (i.e. … by @tocosonic in #2
• switch charging off on phase change is handled by the charger; take the car batterie's state-of-charge into account by @tocosonic in #3
• Integration of BMW cardata service by @tocosonic in #1

New Contributors

• @tocosonic made their first contribution in #2

Full Changelog: 1.2.1...1.3.0