Follow-up to #126.

- Fix the XDG directory flag that got removed with JarSplice. To enable XDG directories, set the 'Use-XDG' property in either build file to 'true'.
- Always re-build jars in the Gradle script (disable "up to date" for the task).
- Delete JarSplicePlus.jar since it's no longer being used.

Signed-off-by: Jeffrey Han <itdelatrisu@gmail.com>

src/itdelatrisu/opsu/objects/curves/Curve.java

@@ -150,6 +150,7 @@ public abstract class Curve {
 	 * @param i the control point index
 	 */
 	public float getY(int i) { return (i == 0) ? y : sliderY[i - 1]; }
+
 	/**
 	 * Discards the slider cache (only used for mmsliders).
 	 */