Decoupling `Base.getSketchbookFolder()` by Stefterv · Pull Request #1334 · processing/processing4

This PR aims to decouple Base.getSketchbookFolder() from all its dependencies

Previously the following was necessary to set up to be able to read the sketchbook folder:

        val resources = File("../resources-bundled/common")
        if (!resources.exists()) {
            throw IllegalStateException("Resources folder not found at ${resources.absolutePath}")
        }
        System.setProperty("processing.resources.folder", resources.absolutePath)
        System.setProperty("java.awt.headless", "true")
        Base.setCommandLine()

        Preferences.init()
        Base.locateSketchbookFolder()

With this PR, one can freely read Base.getSketchbookFolder() and all of the required initialisation will happen automatically. e.g.

val folder = Base.getSketchbookFolder()

It will also clean up the double reference to Processing's language files by just including them in the resources system.
I would prefer to use java's resources going forward and try to move away from the bundled folder.

In general there would need to be a push towards cleaning up the side-effects of a lot of these files but that is very much out of scope for now and this way I can continue building on top of the existing infrastructure.