New config file routines and some fixes

- Bigger bypasses of control routines when the control has been
overridden
- Individual config files for turbines and reactors. Persistent between
reboots, remembers your last saved settings.
- Cruise mode override bypass
- Changing flow rate no longer toggles flow rate override on and off.
Changing the flow rate clearly indicates intent, so we put the override
flag on and leave it there.
- Changed the rate at which the regular algorithm adjusts reactor rod
control rates. Instead of being 1:1 we now move at 1:5 speed because
there is a wide loophole where big adjustments can cause a swinging
pendulum effect continually missing the target.