Setup/remove a reboot schdule

Description: Purpose: Use a config file to schedule system(s) reboots.
Setup:
reboot_at setup
(setup cron and make a backup of crontab, create cron entry)

reboot_at cronjob reads config file, if rightnow > command_time;
then remove $config, create $statfile, reboot
If the script detects $statfile file, the system had already
rebooted, and it won't reboot the systems one more time

Reset and remove the setup:
reboot_at reset
(recover original crontab)

reboot_at cleanup
(clean up everything)

Contact: N/A

Submitter: Steven Ho