Move Nix files back to the root of the project

pkgs/displayselect/default.nix

@@ -0,0 +1,30 @@
+{ pkgs, ... }:
+
+with pkgs;
+
+stdenv.mkDerivation {
+  pname = "displayselect";
+  version = "0.1.0";
+
+  src = fetchFromGitHub {
+    owner = "lukesmithxyz";
+    repo = "voidrice";
+    rev = "master";
+    sha256 = "u4iy2p9i5ORLHcKmAOHVJNaKfYbt+SYUYKblgsRevN8=";
+  };
+
+  buildInputs = [
+    bash
+    xorg.xrandr
+  ];
+
+  patches = [ ./scaling.patch ];
+
+  installPhase = ''
+    mkdir -p $out/bin
+    cp .local/bin/displayselect $out/bin
+    chmod +x $out/bin/displayselect
+  '';
+
+  meta.mainProgram = "displayselect";
+}