hardware: Shift register clears on low, not on high

Signed-off-by: Kai Blin <kai@samba.org>
hardware: We're only using a single shift register after all

Signed-off-by: Kai Blin <kai@samba.org>
server: Move to a fully callback-based logic in handleTravel

Signed-off-by: Kai Blin <kai@samba.org>
server: Larger delay when traveling

Signed-off-by: Kai Blin <kai@samba.org>