Add Docs on VS Code to debug Node-RED and nodes

[Moosbueffel]

Many, many thanks @Steve-Mcl

This will be a great step ahead in my developments. It's not like developing in a real IDE like JAVE,C#,.... because it is not bidirectional (e.g. change a variable and go ahead, or edit source), but it helps a lot to test, understand and find errors.

Or is there perhaps also a trick to use this editor to write a function for node red? I mean to make the file/script writable? So I can edit in VS code and have it than in node red also?