Add anime-launcher, remove commented code in flake

Add anime-launcher because it needs to be installed at the system level
to interact with /etc/hosts configuration.

Remove commented code as it wasn't being used to overlay packages, and
can be easily researched later

systems/onizuka/default.nix

@@ -6,5 +6,6 @@
     ./hardware.nix
     ../../modules/graphics/nvidia
     ../../modules/etc/steam
+    ../../modules/etc/anime-launcher
   ];
 }