patch 8.1.0457: win32 console: key mappings don't work

Problem:    Win32 console: key mappings don't work.
Solution:   Use another solution for the keypad keys that doesn't break
            mappings. Some values will be negative. (Mike Williams)
diff --git a/src/version.c b/src/version.c
index 926efea..f701c25 100644
--- a/src/version.c
+++ b/src/version.c
@@ -793,6 +793,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    457,
+/**/
     456,
 /**/
     455,