Merge pull request #114 from zerginator/master

Fix for normalisationPregain CastException

Author: devgianlu

core/src/main/java/xyz/gianlu/librespot/FileConfiguration.java

@@ -151,7 +151,14 @@ public boolean preloadEnabled() {
 
     @Override
     public float normalisationPregain() {
-        return config.get("player.normalisationPregain");
+        float result;
+        Object raw = config.get("player.normalisationPregain");
+
+        if(raw instanceof Double)  result = ((Double) raw).floatValue();
+        else if(raw instanceof Integer) result = ((Integer) raw).floatValue();
+        else throw new IllegalArgumentException(" normalisationPregain is not a valid number: " + raw.toString());
+
+        return result;
     }
 
     @NotNull