Add a setup-hook to ocamlPackages.eliom, to look for distillery templates

pkgs/development/ocaml-modules/eliom/default.nix

···
 
   createFindlibDestdir = true;
 
+  setupHook = [ ./setup-hook.sh ];
+
   meta = {
     homepage = http://ocsigen.org/eliom/;
     description = "Ocaml Framework for programming Web sites and client/server Web applications";

pkgs/development/ocaml-modules/eliom/setup-hook.sh

···
+addOcsigenDistilleryTemplate() {
+    addToSearchPathWithCustomDelimiter : ELIOM_DISTILLERY_PATH $1/eliom-distillery-templates
+}
+
+envHooks+=(addOcsigenDistilleryTemplate)