0.7.0 introduce storing settings in nvs

- setpoints and factor and ch-setpoint
- also adjust max value and init values

0.6.4 hysteresis2 adjust and send OT to boiler always

- without OT messsages, boiler will decide to burn
- increase hys2 from 0.02 to 0.05
- fix init value of ffactor

0.6.3 don't send OT messages until heater is initialised

- it takes 50s before heater function is first run
- apply a small hysteresis to heater2 early heating activation point

0.6.2 remove clipping of room setpoint if upstairs is warmer than living

- this means upstairs can tune down the demand if it warms up in this
situation
- change hysteresis of heater1 from 0.2 to 0.1 degrees C

0.6.1 do not allow csp below 20

- it even managed to become -1 sending wrong value to opentherm CiC

0.6.0 make upstairs heater algorithm dumb so Quatt can be smart

- hypothesis is that CiC will reduce compressor level according to need
- so when there is overshoot, but outside is cold, choose the level for
maintain
- this is an experiment, so success not guaranteed...
- changed heater factor reset value to 105 = no restriction
- changed CSP base default value to 30

0.5.3 make CH Set Point depend on outside temperature S3

- Homekit chsetpoint used as base, default 35
- if heater==1, CSP=base-S3/2
- if heater==2, CSP=base-S3*2

0.5.2 increase CHsetpoint of boiler with 2 degrees

- might prevent missing a switch-off detection of CiC

0.5.1 use CHsetpoint also for boiler

- else the boiler will overshoot and CiC will shut it down

0.5.0 make CHsetpoint to Quatt/CiC a characteristic

- for experimental reasons, manual control
- was static 35 degrees Celcius, but boiler would stay off...