Fix inconsistency in websocket notifications.
Fix inconsistency in websocket notifications.

For sensor added and deleted websocket notification, place `id` at top
level instead of under `sensor` object.   It’s at top level for light
and group added and deleted events, and for all changed events.

dresden-elektronik/deconz-rest-plugin,dresden-elektronik/deconz-rest-plugin,dresden-elektronik/deconz-rest-plugin,dresden-elektronik/deconz-rest-plugin,dresden-elektronik/deconz-rest-plugin