Implement a true "Group by device"

[ankushg]

Currently, "Group by device" actually groups by entity type (see #631 )

If I have a security camera with a built-in floodlight, I have

• one Device in HA (the camera)
• multiple Entities from that device: a light, a camera, motion sensor, etc

I would like a grouping mode that groups all entities related to the same device together.

This is especially useful for complex devices with a ton of different types of entities - it's hard to design a card that includes everything when the entities are spread out all over the place!

[andyrak]

+1 to this. While the current "Group by device" entity type is nice, I have many cases like @ankushg mentioned.

Having the entities grouped by parent device would be incredibly helpful in my dashboard organization.