update the active source status correctly after a manual switch to another source. closes #124
cosmetics
added vendor id for Denon
sync with LibCecSharp
rpi: don't try to re-register a logical address when the logical address isn't registered and we receive a VC_CEC_LOGICAL_ADDR_LOST message from the firmware. issue #109
rpi: don't wait for a response (and fail) when opening a connection. issue #109
don't send deck status updates to philips when activating the source
don't send two active source message sequences to philips. issue #118