Allow rating songs with just 1 star

Instead of rating songs out of 5 stars, be able to to just “star” a song.

This would essentially add the ability to like a song, without me having to actually rate it out of 5.

This makes it easier for me to keep an updated “<3 Tracks” playlist.

Plexamp has this feature. Maybe they just rate the song 5/5 behind the scenes and abstract it away from me the user.