Added flipX and flipY to loadSpriteFromXML() (#487)

Fixes #478

* Added flipX and flipY to loadSpriteFromXML()

why was this not already implemented? Nevermind I'm pretty sure it's because parseBool isn't a thing

* WHOOPS

gotta update my heckin repo

* Wow neo is good at simplifying stuff

rip parseBool but HAXE MAKE IT A THING

* sigma

¯\_(ツ)_/¯

* Allow for flipx and flipy

as opposed to flipX and flipY (cammel text)

* gaming chair

🪑

---------

Co-authored-by: ⍚~Nex <87421482+NexIsDumb@users.noreply.github.com>

source/funkin/backend/utils/XMLUtil.hx

@@ -143,6 +143,8 @@ class XMLUtil {
 			var graphicSizey:Null<Int> = Std.parseInt(node.att.graphicSizey);
 			if (graphicSizey.isNotNull()) spr.setGraphicSize(0, graphicSizey);
 		}
+		if (node.has.flipX) spr.flipX = node.att.flipX == "true";
+		if (node.has.flipY) spr.flipY = node.att.flipY == "true";
 		if (node.has.updateHitbox && node.att.updateHitbox == "true") spr.updateHitbox();
 
 		if (node.has.zoomfactor)
@@ -392,4 +394,4 @@ typedef BeatAnim = {
 
 interface IXMLEvents {
 	public function onPropertySet(property:String, value:Dynamic):Void;
-}
+}