patch 8.1.0959: sorting large numbers is not tested

Problem:    Sorting large numbers is not tested and does not work properly.
Solution:   Add test.  Fix comparing lines with and without a number.
            (Dominique Pelle, closes #4017)

src/version.c

@@ -779,6 +779,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    959,
 /**/
     958,
 /**/