updated for version 7.4.646

Problem:    ":bufdo" may start at a deleted buffer.
Solution:   Find the first not deleted buffer. (Shane Harper)

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    646,
 /**/
     645,
 /**/