patch 7.4.1502

Problem:    Writing last-but-one line of buffer to a channel isn't implemented
            yet.
Solution:   Implement it.  Fix leaving a swap file behind.

src/version.c

@@ -743,6 +743,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1502,
 /**/
     1501,
 /**/