Make 2013/birken restore sanity after exit

As long as the program (alt code and otherwise) runs to completion the
program will return instead of 0:

    system("reset");

so that the terminal becomes sane again (otherwise cursor is invisible).
One could also use 'tput cvvis' but this is longer and I wanted to make
the column as close to the original ending as possible.

2013/birken/try.sh

@@ -18,7 +18,7 @@ if [[ -z "$BIRKEN" ]]; then
     BIRKEN="birken.alt"
 fi
 
-trap "clear; exit" SIGINT
+trap 'reset; exit' 0 1 2 3 15
 
 for i in *.txt; do
     NAME="$(echo "$i" | awk '{ print toupper(substr($1,1,1)) substr($1,2)}'|sed -e 's/\.txt//g' \