patch 8.0.0177: BufEnter autocommand not fired for a directory

Problem:    When opening a buffer on a directory and inside a try/catch then
            the BufEnter event is not triggered.
Solution:   Return NOTDONE from readfile() for a directory and deal with the
            three possible return values. (Justin M. Keyes, closes #1375,
            closes #1353)
diff --git a/src/version.c b/src/version.c
index c7e47fa..a0887dd 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    177,
+/**/
     176,
 /**/
     175,