Feature request: Add environment variable to rename spotify device name

[ChrisMoriarty]

It would be cool if we could rename the device from "aoede" in Spotify to our own custom name (ex: Music Llama).

[codetheweb]

Happy to accept a PR for this.

[ChrisMoriarty]

Decided to give this a try, although I'm new to Rust and the open source world. Here's the PR:
#53