[orx-parameters, orx-property-watchers, orx-file-watcher, orx-gui] Add @PathParameter, file watcher delegates and property delegates

orx-property-watchers/src/jvmMain/kotlin/ImagePath.kt

@@ -0,0 +1,20 @@
+package org.openrndr.extra.propertywatchers
+
+import org.openrndr.Program
+import org.openrndr.draw.ColorBuffer
+import org.openrndr.draw.loadImage
+import java.io.File
+import kotlin.reflect.KProperty0
+
+fun Program.watchingImagePath(pathProperty: KProperty0<String>, imageTransform: (ColorBuffer) -> ColorBuffer = { it }) =
+    watchingProperty(pathProperty, cleaner = { it.destroy() }) {
+        val file = File(it)
+        require(file.exists()) { "$it does not exist" }
+        require(file.isFile) { "$it is not a file" }
+        val image = loadImage(file)
+        val transformedImage = imageTransform(image)
+        if (image != transformedImage) {
+            image.destroy()
+        }
+        transformedImage
+    }