Updated architecture drawing in README
Updated architecture drawing in README

shmick/HeaterMeter,shmick/HeaterMeter,CapnBry/HeaterMeter,CapnBry/HeaterMeter,CapnBry/HeaterMeter,CapnBry/HeaterMeter,shmick/HeaterMeter,shmick/HeaterMeter,shmick/HeaterMeter,CapnBry/HeaterMeter,shmick/HeaterMeter,shmick/HeaterMeter,CapnBry/HeaterMeter,CapnBry/HeaterMeter