Remove duplicated nixpkgs-overlay directory

also some changes where missing which only existed in overlay

nixpkgs-overlay/bmxd.nix

@@ -1,31 +0,0 @@
-{ stdenv, fetchgit, fetchpatch, }:
-
-let
-  src = fetchgit {
-    url = "https://gitlab.freifunk-dresden.de/firmware-developer/firmware.git";
-    sha256 = "sha256-3sV59uqFp+TZKrDf7kmksLvz+5ZKriwFyXZMBH2Sdws=";
-  };
-  path = "feeds/19.07/feeds-own/bmxd";
-  makefile = builtins.readFile "${src}/${path}/Makefile";
-  makeDef = name:
-    builtins.elemAt (builtins.match ''
-      .*?${name}:=([^
-      ]+).*?'' makefile) 0;
-  name = makeDef "PKG_NAME";
-  version = makeDef "PKG_VERSION";
-  release = makeDef "PKG_RELEASE";
-  patch = fetchpatch {
-    name = "timercpy.patch";
-    url =
-      "https://gitlab.freifunk-dresden.de/firmware-developer/firmware/merge_requests/36.patch";
-    sha256 = "sha256-40BbcCZ10cQzvkfsAi8ApCgmC4hGMh2J8xU6gjD3cng=";
-  };
-in stdenv.mkDerivation {
-  name = "${name}-${version}-${release}";
-  inherit src;
-  patches = [ patch ];
-  buildPhase = "cd ${path}/sources";
-  installPhase = ''
-    make install SBINDIR=$out/sbin
-  '';
-}

nixpkgs-overlay/default.nix

@@ -1,9 +0,0 @@
-final: prev:
-
-{
-
-  bmxd = prev.callPackage ./bmxd.nix { };
-
-  pile = prev.callPackage ./pile.nix { };
-
-}

nixpkgs-overlay/pile.nix

@@ -1,25 +0,0 @@
-{ fetchgit, rustPlatform }:
-
-let
-  pile = fetchgit {
-    url = "https://github.com/astro/pile.git";
-    sha256 = "sha256-z4xNUGmP35ZBZUpgozQHANZniADfmwEoclnEwNlvAC4=";
-  };
-in {
-  ledball = rustPlatform.buildRustPackage {
-    name = "ledball";
-    version = "0.0.0";
-    src = "${pile}/ledball";
-    cargoSha256 = "0zyfbf3gph8gqab07fmm5a7x5slapsqn8ck6isp53fsa7ljnagjy";
-    cargoBuildFlags = [ "--examples" ];
-    postInstall = ''
-      mkdir -p $out/bin
-
-      for f in target/*/release/examples/*; do
-        if [ -f $f ] && [ -x $f ]; then
-          cp $f $out/bin/
-        fi
-      done
-    '';
-  };
-}