Feature request protocol version

[ghost]

Hi, thanks for your good work on writing this ha-integration!

I had a small issue to get it to work though. My devices are using the 3.3 protocol. At line 100 I had to add self._device.set_version(3.3) in order to get it running.

def __init__(self, device):
        """Initialize the cache."""
        self._cached_status = ''
        self._cached_status_time = 0
        self._device = device
        self._device.set_version(3.3)
        self._lock = Lock()

It would be nice if you can set the protocol-version in the in the .yaml (like voltage/current)

Cheers!