replace InputEvent references with GlobalScope in joystick doc
Created by: Hinsbart
When I originally wrote this, I was used to the c++ side of things where the JOY_*
constants are defined in InputEvent.h. But in gdscript, they are actually bound to the global scope.
When looking for how to reference Global Scope, I found one other usage in add_user_signal
. Well, apparently that was not the right way to do it :P
So I also fixed that one.