[DESIGN.md: Launchers] Rename kfmon.ini to wallabako.ini

Hi!

On the DESIGN.md page at launchers section, the command for the config file sould be (for preserving the KFMon deamon config):

cp assets/kfmon.ini /media/anarcat/KOBOeReader/.adds/kfmon/config/wallabako.ini

in place of

cp assets/kfmon.ini /media/anarcat/KOBOeReader/.adds/kfmon/config/

Maybe it would be better to change the file name in the repo rather than when copying by the user, but I just modified the DESIGN.md for now.