I want Echo to play a short sound when a motion is detected, e.g. say "Hello" when a person goes by. I have a motion sensor connected to Wink hub, I bought Echo and connected with Wink. Echo can control my Wink devices, but I want it go the other way. I am a software developer and want to understand whether Echo/Alexa API has capability to play a sound on an external command. Can the Echo/Alexa system receive any input or it is only to voice-control other things?