Extend pre-warm before scheduled on a little.
Extend pre-warm before scheduled on a little.

Previous 1h may simply not be enough in many cases,
even at risk of waking people or catching them by surprise,
a little longer seems prudent.
opentrv/OpenTRV-Arduino-V0p2,opentrv/OpenTRV-Arduino-V0p2,opentrv/OpenTRV-Arduino-V0p2