Change command argument parsing logic.
Change command argument parsing logic.

To simplify and change the priority of optional arguments.

woss/koko,noraesae/koko,KokoIRC/koko,noraesae/koko,hachibasu/koko,woss/koko,KokoIRC/koko,KokoIRC/koko,alienxp03/koko,woss/koko,alienxp03/koko,hachibasu/koko,noraesae/koko,hachibasu/koko,alienxp03/koko