updated for version 7.3.021

Problem:    Conflict for defining Boolean in Mac header files.
Solution:   Define NO_X11_INCLUDES. (Rainer Muller)

src/version.c

@@ -714,6 +714,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    21,
 /**/
     20,
 /**/