Added
- A device is created in Home Assistant in the room of its channels. The
discovery config carries the room as the device'ssuggested_area(task
18). It did so before only when every channel of the device lay in one and
the same room: a device with channels in two rooms got no area, and on
openccu-lite, whose rooms can be nested and whose room list of a channel
names the parents too (Küche,Erdgeschoss), no device got one at all.
Now the area is the room shared by all channels of the device that lie in a
room, otherwise the room of the lowest-numbered channel that lies in one; a
channel in several rooms counts with its first (on openccu-lite the most
specific), and a room of the device itself comes first. The rooms are the
ReGaHSS's on a CCU and the system's metadata's on openccu-lite. New option
Suggest the channel's room as the device's area on the node, on by
default. Home Assistant applies the suggestion only when it first creates
the device; a room changed later stays as assigned in Home Assistant.