Add Warnings to the JAX-WS and JAXB tools indicating they are deprecated

It was suggested that we should add a simple warning message to the JAXWS and JAXB tools indicating that the tools have been deprecated and may be removed.

The proposed change is:

$ hg diff
diff -r 3eae36c6baa5 src/jdk.xml.bind/share/classes/com/sun/tools/internal/jxc/SchemaGenerator.java
--- a/src/jdk.xml.bind/share/classes/com/sun/tools/internal/jxc/SchemaGenerator.java Tue Jan 23 12:23:55 2018 +0000
+++ b/src/jdk.xml.bind/share/classes/com/sun/tools/internal/jxc/SchemaGenerator.java Wed Jan 24 12:29:34 2018 -0500
@@ -64,6 +64,8 @@
      * Runs the schema generator.
      */
     public static void main(String[] args) throws Exception {
+ System.out.println("WARNING: schemagen has been deprecated and will be removed in a future release!");
+
         System.exit(run(args));
     }
 
diff -r 3eae36c6baa5 src/jdk.xml.bind/share/classes/com/sun/tools/internal/xjc/Driver.java
--- a/src/jdk.xml.bind/share/classes/com/sun/tools/internal/xjc/Driver.java Tue Jan 23 12:23:55 2018 +0000
+++ b/src/jdk.xml.bind/share/classes/com/sun/tools/internal/xjc/Driver.java Wed Jan 24 12:29:34 2018 -0500
@@ -125,6 +125,8 @@
     }
 
     private static void _main( String[] args ) throws Exception {
+ System.out.println("WARNING: xjc has been deprecated and will be removed in a future release!");
+
         try {
             System.exit(run( args, System.out, System.out ));
         } catch (BadCommandLineException e) {
diff -r 3eae36c6baa5 src/jdk.xml.ws/share/classes/com/sun/tools/internal/ws/wscompile/WsgenTool.java
--- a/src/jdk.xml.ws/share/classes/com/sun/tools/internal/ws/wscompile/WsgenTool.java Tue Jan 23 12:23:55 2018 +0000
+++ b/src/jdk.xml.ws/share/classes/com/sun/tools/internal/ws/wscompile/WsgenTool.java Wed Jan 24 12:29:34 2018 -0500
@@ -94,6 +94,7 @@
     }
 
     public boolean run(String[] args) {
+ System.out.println("WARNING: wsgen has been deprecated and will be removed in a future release!");
         final Listener listener = new Listener();
         for (String arg : args) {
             if (arg.equals("-version")) {
diff -r 3eae36c6baa5 src/jdk.xml.ws/share/classes/com/sun/tools/internal/ws/wscompile/WsimportTool.java
--- a/src/jdk.xml.ws/share/classes/com/sun/tools/internal/ws/wscompile/WsimportTool.java Tue Jan 23 12:23:55 2018 +0000
+++ b/src/jdk.xml.ws/share/classes/com/sun/tools/internal/ws/wscompile/WsimportTool.java Wed Jan 24 12:29:34 2018 -0500
@@ -170,6 +170,7 @@
 
     protected boolean run(String[] args, Listener listener,
                        Receiver receiver) {
+ System.out.println("WARNING: wsimport has been deprecated and will be removed in a future release!");
         for (String arg : args) {
             if (arg.equals("-version")) {
                 listener.message(
$