Pipes Erc messages to a TTS program.
Use via M-x erc-tts-start. The "TTS program" must be a executable that reads lines to speak on STDIN and outputs sound to your system's preferred sound sink.
The TTS process can be stopped using M-x erc-tts-stop.
Defines an interactive mpris2-yank-current-track function that inserts the current MPRIS2 track & artist name at point.