Refactored and reformatted code to use less static variables

src/main/java/eu/crushedpixel/replaymod/holders/PositionKeyframe.java

@@ -2,19 +2,14 @@ package eu.crushedpixel.replaymod.holders;
 
 public class PositionKeyframe extends Keyframe {
 
-	private Position position;
-	
-	public PositionKeyframe(int realTime, Position position) {
-		super(realTime);
-		this.position = position;
-	}
+    private final Position position;
 
-	public Position getPosition() {
-		return position;
-	}
+    public PositionKeyframe(int realTime, Position position) {
+        super(realTime);
+        this.position = position;
+    }
 
-	public void setPosition(Position position) {
-		this.position = position;
-	}
-	
+    public Position getPosition() {
+        return position;
+    }
 }