Signal K support for fields from Engine Configuration Status

[fabdrol]

Recently I needed to represent additional engine information from PGN 127498 (Engine Configuration Status). These fields are not yet present in Signal K. This is how the canboat output looks:

const ex = {
   "pgn":127498,
   "description":"Engine Configuration Status",
   "fields":{
      "Instance": "Single Engine or Dual Engine Port",
      "Rated Engine Speed": 800,
      "VIN": "17 character VIN.",
      "Engine Software Revision Number"
   }
}

I would like to propose the following new. If nobody objects, I'll do PRs for n2k-signalk and specification

• propulsion.<inst>.ratedRevolutions
• propulsion.<inst>.vehicleIdentificationNumber
• propulsion.<inst>.softwareId

Thoughts?

[tkurki]

LGTM