Initial Contribution for OH2 Max!Cube binding

Signed-off-by: Marcel Verpaalen <marcel@verpaalen.com>
Now this is weird - when defining a thing instance, either the IP or the serial number must be provided, otherwise it does not make sense (note that you must not take discovery into account here as it is just a means of providing the required input). So if a user wants to manually add a cube, what would you ask him to enter? The IP or the serial number? Assuming that he might want to do it manually, because the discovery does not work for some reason, the IP is probably the safer thing to choose, right? At least that's how it is done in the Hue binding as well.