Add spec/schema for the runtime definition format

[jonnor]

We rely on a standard format for runtime information in the client (typically serialized as JSON)

label: "MicroFlo Simulator"
description: "The first component in the world"
type: "microflo"
protocol: "websocket"
address: "ws://localhost:3333"
secret: "microflo32"
id: "2ef763ff-1f28-49b8-b58f-5c6a5c23af2d"
user: "3f3a8187-0931-4611-8963-239c0dff1931"

This is used also when registering with Flowhub, and is proposed to use in fbp-spec and fbp-protocol tester for runtime information.

[jonnor]

Should maybe be moved to https://github.com/flowbased/fbp-protocol

[bergie]

https://github.com/flowbased/fbp-client/blob/master/schema/definition.json