Waits for a signal, plays a sound and sends a pushover message to mobile devices.
For Ogg playback:
sudo apt-get install vorbis-tools
Doorbell audio taken from http://commons.wikimedia.org/wiki/File:Doorbell-cheap-dingdong.ogg
If you get this error: Error: ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.front
Edit /usr/share/alsa/alsa.conf change the line pcm.front cards.pcm.front to pcm.front cards.pcm.default