improves car.py reliability, condense can.py&db.py->db.py

car.py is now triple-process. Main process spawns a hephaestus and
hermes process. Hephaestus read pkts and writes to car-rmq, hermes
consumes car-rmq pkts and produces laptop-rmq packets.
Also chris if you see this, it's 5am --> i may sleep in tomorrow