Minor fix in 1998/chaos - restore terminal at exit

The problem with not calling 'endwin()' is that echo will be disabled
which is a problem for the user if they don't know to type stty echo or
reset or stty sane.

1998/chaos/README.md

@@ -18,6 +18,9 @@ Or you can build this entry without the `halfdelay()` call by:
 
 	make chaos_nohalf
 
+[Cody Boone Ferguson](/winners.html#Cody_Boone_Ferguson) added a call to
+`endwin()` to restore terminal sanity (echo etc.) when exiting the program.
+Thank you Cody for your assistance!
 
 ## To run: