delete wake timers when the program exits

[RoguedBear]

if the user exits the program (ctrl+c) then delete the wake timers that might be there if the program was in sleep state.
If the wake timer was for a sufficiently large duration and the user puts the computer to sleep, the machine could wake up undesirably and deplete battery (if laptop).

as of now, i haven't been able to find a way to delete waketimers in linux, so if you face this specific issue just dont use sleep_interval key in config.yaml