[hm] Switch config loaders to use a union to save stack space and shrink code size
[hm] Switch config loaders to use a union to save stack space and shrink code size

CapnBry/HeaterMeter,shmick/HeaterMeter,dwright134/HeaterMeter,kdakers80/HeaterMeter,dwright134/HeaterMeter,shmick/HeaterMeter,kdakers80/HeaterMeter,CapnBry/HeaterMeter,dwright134/HeaterMeter,kdakers80/HeaterMeter,kdakers80/HeaterMeter,shmick/HeaterMeter,kdakers80/HeaterMeter,dwright134/HeaterMeter,kdakers80/HeaterMeter,shmick/HeaterMeter,dwright134/HeaterMeter,dwright134/HeaterMeter,shmick/HeaterMeter,shmick/HeaterMeter,CapnBry/HeaterMeter,CapnBry/HeaterMeter,shmick/HeaterMeter,CapnBry/HeaterMeter,CapnBry/HeaterMeter,CapnBry/HeaterMeter