Why we should include this into the repository? It's a very clean and modern note-taking app, and looks promising. Nothing innovative, but looks like a nice addition.
Is it open source? Yes, Mozilla 2.0: https://github.com/nuttyartist/notes/blob/dev/LICENSE
Most up to date, versioned source tarball/zipfile: https://github.com/nuttyartist/notes/archive/v1.0.0.zip