Korge: View - Implement addTo mutable list function (#2349)

Similar to https://github.com/korlibs/korge/blob/7485aae1ba8cb9d0b7ecc2853861f07cc5ff4204/korge/src/korlibs/korge/view/Container.kt#L554

Co-authored-by: jobeGameDev <[email protected]>

Author: FSaurenbach

korge/src/korlibs/korge/view/View.kt

@@ -1568,6 +1568,11 @@ fun <T : View> T.onNextFrame(block: T.(views: Views) -> Unit): CloseableCancella
     return closeable
 }
 
+/** Add an arbitrary view to a mutable list. */
+fun <T : View> T.addTo(parent: MutableList<in T>): T {
+    parent += this
+    return this
+}
 
 // @TODO: Replace width, height with SizeInt
 fun <T : View> T.onStageResized(firstTrigger: Boolean = true, block: Views.(width: Int, height: Int) -> Unit): T = this.apply {