Fix double reboot #17

The LiFePO4wered Pi+ likes to do a hard reboot whenever we do a soft reset, but it's slow so we end up rebooting to Linux, then having Linux reboot. This is awful. I think it may be fixed by doing 'lifepo4wered-cli write shdn_delay 65535', so the hard reboot never comes by the time we boot back in to Linux with the lifepo4wered-daemon running. We also need to decide if we want to keep 'lifepo4wered-cli write pi_boot_to 0' which disables turning the machine off if the daemon doesn't come up. Either way we should document all this.

I also needed to set 'lifepo4wered-cli write pi_shdn_to 0' today to fix it resetting after boot. This is only useful for development since it breaks powering off.