patch 8.1.0731: JS encoding does not handle negative infinity

Problem:    JS encoding does not handle negative infinity.
Solution:   Add support for negative infinity for JS encoding. (Dominique
            Pelle, closes #3792)

src/version.c

@@ -795,6 +795,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    731,
 /**/
     730,
 /**/