Remove Harmony music player

Harmony did not receive any update since changing from FOOS to a Sublime Text like freeware/paid model, with last update coming almost 3 years ago (AUR package was updated to v0.9.1 on 2018-03)

README.md

@@ -93,7 +93,6 @@
 - [![Open-Source Software][OSS Icon]](https://github.com/MarshallOfSound/Google-Play-Music-Desktop-Player-UNOFFICIAL-) [Google Play Music Desktop Player](https://www.googleplaymusicdesktopplayer.com/) - Unofficial but beautiful cross-platform desktop player for Google Play Music.
 - [![Open-Source Software][OSS Icon]](https://github.com/gpodder/gpodder) [Gpodder](https://gpodder.github.io/) - Media aggregator and podcast client.
 - [![Open-Source Software][OSS Icon]](https://github.com/haecker-felix/Gradio) [GRadio](https://github.com/haecker-felix/gradio/releases/) - Radio software for Ubuntu Linux.
-- [Harmony](https://getharmony.xyz) - Music player with sleek interface & cloud compatibility.
 - [![Open-Source Software][OSS Icon]](https://github.com/mtytel/helm) [Helm](https://tytel.org/helm/) - A software synthesizer, that runs either standalone, or as an LV2, VST, VST3 or AU plugin.
 - [![Open-Source Software][OSS Icon]](https://github.com/hydrogen-music/hydrogen) [Hydrogen](http://www.hydrogen-music.org/) - Advanced drum machine for GNU/Linux.
 - [![Open-Source Software][OSS Icon]](https://github.com/trazyn/ieaseMusic) [ieaseMusic](https://github.com/trazyn/ieaseMusic) - iEaseMusic is a multiplatform program built in electron for listening to NetEase Music.