Fix infinite loop in 1992/vern

If one entered input < 0 || > 077 (octal) the program would enter an
infinite loop that flooded the screen, forcing the user to terminate the
program.

The problem was that scanf(3) (with "%o %o" specifier string) was in a
loop checking for return value of 2 (this was not a problem because
scanf(3) does not return until all the specifiers are processed or I
suppose some error occurs) and not checking the values. Instead it just
checked a function on the numbers. This fix involves using scanf(3) with
the specifier "%4s %4s" and then using strtol(3) with base 8 and then
checking for < 0 || > 077 (using "%o %o" will not work).

The game now functions as expected without flooding the terminal if
invalid input is given. The judges' remarks about the range has been
kept in as it's still invalid it just won't flood the screen.

bugs.md

@@ -946,22 +946,6 @@ it can 'rub your nose in defeat', as the author puts it. You will have to exit
 it yourself through ctrl-c or killing it in some other fashion.
 
 
-### STATUS: known bug - please help us fix
-
-If one enters a number out of range, that is < 00 or > 77, the program will
-enter an infinite loop, flooding the screen.
-
-You are welcome to try and fix this (mis)feature. It might help if you run the
-intermediate step in compilation like so:
-
-```sh
-sed <vern.c 's/{ /(/g;s/} /)/g;s/;       /#define /' | \
-    sed 's/}      /=/g;s/{        /i/g' >vern.tmp.c
-```
-
-and look at `vern.tmp.c` instead, to give you an idea of what is going on.
-
-
 ## 1992 westley
 
 ### STATUS: INABIAF - please **DO NOT** fix