updated for version 7.4.539

Problem:    Crash when computing buffer count.  Problem with range for user
            commands.  Line range wrong in Visual area.
Solution:   Avoid segfault in compute_buffer_local_count().  Check for
            CMD_USER when checking type of range. (Marcin Szamotulski)

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    539,
 /**/
     538,
 /**/