patch 8.0.1774: reading very long lines can be slow

Problem:    Reading very long lines can be slow.
Solution:   Read up to 1 Mbyte at a time to avoid a lot of copying.  Add a
            check for going over the column limit.
diff --git a/src/version.c b/src/version.c
index 5d75dab..10e446a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1774,
+/**/
     1773,
 /**/
     1772,