Do not track JmeVersion as it is autogenerated

jme3-core/src/main/java/com/jme3/system/JmeVersion.java

@@ -1,14 +0,0 @@
-
-package com.jme3.system;
-
-/**
- * THIS IS AN AUTO-GENERATED FILE..
- * DO NOT MODIFY!
- */
-public class JmeVersion {
-    public static final String BUILD_DATE = "unknown";
-    public static final String BRANCH_NAME = "unknown";
-    public static final String GIT_HASH = "unknown";
-    public static final String GIT_SHORT_HASH = "unknown";
-    public static final String FULL_NAME = "jMonkeyEngine 3.1.0 (snapshot-github)";
-}