updated for version 7.4.456

Problem:    'backupcopy' is global, cannot write only some files in a
            different way.
Solution:   Make 'backupcopy' global-local. (Christian Brabandt)

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    456,
 /**/
     455,
 /**/