Auto add include statement when undefined function reference is detected.

[genius257]

Easy implementation is to simply add this feature for the standard files in the AutoIt include directory, to avoid too much IO.
Alternative is to once scan and map all files in Standard library, User-defined libraries and workspace.
Watching the folders for changes if possible would be a plus.

See https://stackoverflow.com/a/53015835/3958400 for inspiration on how to trigger.