Implement java interface for RS shutdown and fix shutdown deadlock with the command fifo.
diff --git a/rsThreadIO.cpp b/rsThreadIO.cpp
index 4a1dbbb..db4bb81 100644
--- a/rsThreadIO.cpp
+++ b/rsThreadIO.cpp
@@ -30,6 +30,11 @@
 {
 }
 
+void ThreadIO::shutdown()
+{
+    mToCore.shutdown();
+}
+
 bool ThreadIO::playCoreCommands(Context *con, bool waitForCommand)
 {
     bool ret = false;