Reapply segfault fixes in 1998/schnitzi

After discussing it with Landon it was recommended that these fixes be
reapplied.

Updated bugs.md wrt this.

README.md has had formatting fixes as well.

Updated URL for author as it has changed. It's very little on his page
and the only page that suggests it is his is the ioccc.html page. I
couldn't find anything else.

bugs.md

@@ -764,15 +764,6 @@ $ ./schnitzi 9|wc -l
   771999
 ```
 
-There are two segfaults that were initially fixed but the fixes were undone to
-make the entry as close to possible as the original. These should not be fixed
-either:
-
-- if one does not specify an arg the program will crash.
-- if the arg had any characters that were not digits 1 - 9 it will show invalid
-output and then crash. If it starts with 0 it can work as long as another digit
-follows it and there are no other non-digits.
-
 
 # 1999