Some work on Scripts

notable changes:
- rename `bt-connect` to `bt_connect`
- rename `music` to `media` and make it generic instead of checking
  Spotify
- make separate script to set background to a preset black image
- make all shebangs "#!/usr/bin/env sh"

Scripts/.local/scripts/black-bg

@@ -0,0 +1,3 @@
+#!/usr/bin/env sh
+
+feh --bg-fill $HOME/Pictures/Backgrounds/black-nice.jpg;