Merged fixes and new functionality into 1.2.1
#19 #18 including thermostats in heater device filter. Looking into how to identify thermostats.
#19 Looking into how to identify thermostats.
#19 first go on trying to facilitate compatibility with other thermostat devices.
#19 #18 #6 updated vnr. implemented function for filtered list of heater devices
#6 Minor bugfix
#19 changed thermostat on mode to heat
#19 #6 Merged changes from 1.2.2b into master branch