Only define MOJOSHADER_VERSION and MOJOSHADER_CHANGESET if required.
External developers might want to retag this, from the compiler command line.
--- a/mojoshader.h Fri Nov 28 04:05:55 2008 -0500
+++ b/mojoshader.h Mon Dec 01 17:54:48 2008 -0500
@@ -17,8 +17,13 @@
/* You can define this if you aren't generating mojoshader_version.h */
#ifndef MOJOSHADER_NO_VERSION_INCLUDE
#include "mojoshader_version.h"
-#else
+#endif
+
+#ifndef MOJOSHADER_VERSION
#define MOJOSHADER_VERSION -1
+#endif
+
+#ifndef MOJOSHADER_CHANGESET
#define MOJOSHADER_CHANGESET "???"
#endif