patch 8.0.1815: crash with terminal window and with 'lazyredraw' set

Problem:    Still a crash with terminal window and with 'lazyredraw' set.
            (Antoine)
Solution:   Do not wipe out the buffer when updating the screen.
diff --git a/src/version.c b/src/version.c
index 918e192..6346e62 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1815,
+/**/
     1814,
 /**/
     1813,