Possibility to add entities for gateways

[AlirezaT]

I have a Bluetooth gateway which is a socket with relay and power measurement. ALUSSO Gateway

• It could be configured as a normal switch and works fine
• As a gateway to control BL-Light:
  The first time trying to toggle the light, the gateway relay gets toggled and then the light is under control properly.
  is there a way to define DP for such a gateway and still use it as Gateway?

that might also fix this conflict.

I've tried to is_gateway: false in configuration.yaml but the BL light becomes unavailable by doing this!

I need to have is_gateway: true & define entities for the Hub at the same time

Originally posted by @AlirezaT in #31 (comment)