Rfxcom Lighting1 doorbell chime

Hi Pauli,

I have added support for the home easy doorbell (Lighting 1 chime). It's tested locally with me. I thought it best to add to your refactored rfxcom.

Commit cc5b53e49e9eb3424698cf456839e3d352787d92 is what you will be interested in. All the other cruft is upstream merges etc (don't know how to avoid this!).

FYI  the rest of my devices working fine (Oregon Sci temp/hum sensors, Lightwave RF (lighting 5) stuff and OWL energy monitor).

Thanks!