add noteOff/chordOff support for Audio Tag (does this sound ok without linear ramping?)
add WebMIDIAPI shim to all the demos

Web MIDI API support works with jazz-soft.net plugin installed, this means users will not need to download Soundfonts from your website, rather they will use their built-in sound banks. This shim by @cwilso provides a preview of the upcoming Web MIDI API, an exciting addition to the W3 specs!