development/interpreters/lua-5: remove unused files

These nix expressions from the lua-5 directory are imported nowhere and
can be removed safely.

pkgs/development/interpreters/lua-5/filesystem.nix

@@ -1,26 +0,0 @@
-{ stdenv, fetchurl, lua5 }:
-
-stdenv.mkDerivation {
-  version = "1.6.2";
-  pname = "lua-filesystem";
-  isLibrary = true;
-  src = fetchurl {
-    url = "https://github.com/keplerproject/luafilesystem/archive/v1_6_2.tar.gz";
-    sha256 = "1n8qdwa20ypbrny99vhkmx8q04zd2jjycdb5196xdhgvqzk10abz";
-  };
-
-  buildInputs = [ lua5 ];
-
-  preBuild = ''
-    makeFlagsArray=(
-      PREFIX=$out
-      LUA_LIBDIR="$out/lib/lua/${lua5.luaversion}"
-      LUA_INC="-I${lua5}/include");
-  '';
-
-  meta = {
-    homepage = "https://github.com/keplerproject/luafilesystem";
-    hydraPlatforms = lib.platforms.linux;
-    maintainers = [ ];
-  };
-}

pkgs/development/interpreters/lua-5/sockets.nix

@@ -1,25 +0,0 @@
-{ stdenv, fetchurl, lua5 }:
-
-stdenv.mkDerivation rec {
-  pname = "lua-sockets";
-  version = "2.0.2";
-  src = fetchurl {
-      url = "http://files.luaforge.net/releases/luasocket/luasocket/luasocket-${version}/luasocket-${version}.tar.gz";
-      sha256 = "19ichkbc4rxv00ggz8gyf29jibvc2wq9pqjik0ll326rrxswgnag";
-  };
-
-  luaver = lua5.luaversion;
-  patchPhase = ''
-      sed -e "s,^INSTALL_TOP_SHARE.*,INSTALL_TOP_SHARE=$out/share/lua/${lua5.luaversion}," \
-          -e "s,^INSTALL_TOP_LIB.*,INSTALL_TOP_LIB=$out/lib/lua/${lua5.luaversion}," \
-          -i config
-  '';
-
-  buildInputs = [ lua5 ];
-
-  meta = {
-    homepage = "http://w3.impa.br/~diego/software/luasocket/";
-    hydraPlatforms = lib.platforms.linux;
-    maintainers = [ ];
-  };
-}