feat (heaters): add low, medium, high, preset_1-3, standby preset_modes
Some heaters have low/medium/high mapped to eco, comfort, boost, but
this is not obvious to new users and takes some getting used to. It
also results in submissions ignoring known presets and using Low,
Medium and High to better match their heater.
Preset 1-3 and Standby were already in use, so could use translations.
Issue #1708