cjdns: python2 -> python3

The `contrib` folder was removed from the packaging. It contains a lot of files
that are irrelevant to the actual package (i.e. Fedora spec files, selinux hardening
or systemd services). There are a few scripts in there too but in any case they are
misplaced and would be better off in a separate package (as e.g. the Fedora packaging
does)

pkgs/tools/networking/cjdns/default.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchFromGitHub, nodejs, which, python27, util-linux, nixosTests }:
+{ lib, stdenv, fetchFromGitHub, nodejs, which, python3, util-linux, nixosTests }:
 
 stdenv.mkDerivation rec {
   pname = "cjdns";
@@ -11,7 +11,7 @@ stdenv.mkDerivation rec {
     sha256 = "NOmk+vMZ8i0E2MjrUzksk+tkJ9XVVNEXlE5OOTNa+Y0=";
   };
 
-  buildInputs = [ which python27 nodejs ] ++
+  buildInputs = [ which python3 nodejs ] ++
     # for flock
     lib.optional stdenv.isLinux util-linux;
 
@@ -21,12 +21,8 @@ stdenv.mkDerivation rec {
     + "bash do";
   installPhase = ''
     install -Dt "$out/bin/" cjdroute makekeys privatetopublic publictoip6
-    sed -i 's,/usr/bin/env node,'$(type -P node), \
-      $(find contrib -name "*.js")
-    sed -i 's,/usr/bin/env python,'$(type -P python), \
-      $(find contrib -type f)
     mkdir -p $out/share/cjdns
-    cp -R contrib tools node_build node_modules $out/share/cjdns/
+    cp -R tools node_build node_modules $out/share/cjdns/
   '';
 
   passthru.tests.basic = nixosTests.cjdns;