Add favicon to binary

[nol166]

For ChromeOS users, it would be neat to have a favicon for the binary so when it's pinned to the taskbar it is easily distinguishable.

[codehz]

I think it is better to implement it as PWA: just add a manifest.json and a simple ServiceWorker

[NGTmeaty]

Active issue at #154 probably should close this?

[nol166]

@NGTmeaty closing