Fix toString of NumberType to be like class name

Author: ljacqu

src/main/java/ch/jalu/configme/properties/types/NumberType.java

@@ -123,7 +123,7 @@ public boolean canConvertToType(@NotNull TypeInfo typeInformation) {
 
     @Override
     public @NotNull String toString() {
-        return "NumberTypeHandler[" + getType().getSimpleName() + "]";
+        return "NumberType[" + getType().getSimpleName() + "]";
     }
 
     /**