This adds a new method: get_remaining_charge which returns a list of values of the battery's remaining charge (in kWh).
- Also some breaking rename changes:
- `get_solar_generation_data` is now `get_solar_generation`
- `latest_solar_generation_data` is now `latest_solar_generation`
- `get_house_data` is now `get_house_consumption`
- `latest_house_data` is now `latest_house_consumption`
These renames were to make the methods more descriptive and meaningful.