Add a flag to note if an identifier came from built-in definitions versus source

[petetronic]

It would be helpful to have a flag in the completions response data that would allow us to note which identifiers came from the .json defs and which were from user .js source files (to help categorize globals as being user code or built-in).

[marijnh]

In patch 503b1ca and 7678c5b I've added support for getting 'origins' with completions, which are the filename that a thing comes from or the !name field of the def file it was loaded in.

You could associate custom icons with the names of the def files that you loaded. Does that help?

[petetronic]

Thanks - this information worked for us!