vim-patch:7.4.491

Problem:    When winrestview() has a negative "topline" value there are
	    display errors.
Solution:   Correct a negative value to 1. (Hirohito Higashi)

https://code.google.com/p/vim/source/detail?r=v7-4-491

src/nvim/version.c

@@ -247,7 +247,7 @@ static int included_patches[] = {
   494,
   493,
   //492,
-  //491,
+  491,
   //490,
   //489,
   //488,