added logger

src/de/miaurizius/jgame2d/core/Sound.java

@@ -6,6 +6,8 @@ import javax.sound.sampled.Clip;
 import java.io.File;
 import java.net.MalformedURLException;
 import java.net.URL;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 public class Sound {
 
@@ -20,7 +22,7 @@ public class Sound {
             soundURL[3] = new File("assets/sounds/unlock.wav").toURI().toURL();
             soundURL[4] = new File("assets/sounds/fanfare.wav").toURI().toURL();
         } catch(MalformedURLException e) {
-            e.printStackTrace();
+            Boot.logger.log(Level.SEVERE, e.getMessage());
         }
     }