Add cooling loop temperature to graphs
Add ambient temperature to graphs
Support for motorised ball valves

Motorised ball valves require one power output to open, and a different
power output to close.  Some of them have limit switches to indicate
whether they are fully open or closed.

A new register 'vtype' is introduced, to set the type of valve attached:

0 or 255 (default) - regular valve: power to open, spring to close
1 - ball valve, power to open and to close, no limit sensors
2 - as (1) but with limit sensors
Option to disable front-panel sensor setup mode