patch 7.4.1993

Problem:    Not all TRUE and FALSE arguments are tested.
Solution:   Add a few more tests.

src/version.c

@@ -758,6 +758,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1993,
 /**/
     1992,
 /**/