Fix for Philips Hue flickering when switchOffOnBlack is set true (#668)
Fix for Philips Hue flickering when switchOffOnBlack is set true (#668)

* Improved switch off on black feature.

* Changed "isnan" to "std::isnan"


Former-commit-id: 5db2b97674661e4e19f796a91dd443a501268e27
ntim/hyperion,Funatiq/hyperion.ng,Funatiq/hyperion.ng,Funatiq/hyperion.ng,penfold42/hyperion.ng,hyperion-project/hyperion.ng,hyperion-project/hyperion,redPanther/hyperion.ng,hyperion-project/hyperion.ng,hyperion-project/hyperion.ng,hyperion-project/hyperion.ng,redPanther/hyperion.ng,redPanther/hyperion.ng,ntim/hyperion,Funatiq/hyperion.ng,hyperion-project/hyperion,penfold42/hyperion.ng,hyperion-project/hyperion.ng,redPanther/hyperion.ng,redPanther/hyperion.ng,penfold42/hyperion.ng,penfold42/hyperion.ng,hyperion-project/hyperion,ntim/hyperion,redPanther/hyperion.ng,penfold42/hyperion.ng,Funatiq/hyperion.ng,hyperion-project/hyperion,hyperion-project/hyperion,ntim/hyperion,Funatiq/hyperion.ng,hyperion-project/hyperion.ng,ntim/hyperion,ntim/hyperion,penfold42/hyperion.ng,hyperion-project/hyperion