kgpg: wrap with path to gpg

Fixes #5697.

pkgs/applications/kde-apps-15.08/kgpg.nix

@@ -2,12 +2,14 @@
 , lib
 , automoc4
 , cmake
+, makeWrapper
 , perl
 , pkgconfig
 , boost
 , gpgme
 , kdelibs
 , kdepimlibs
+, gnupg
 }:
 
 kdeApp {
@@ -15,6 +17,7 @@ kdeApp {
   nativeBuildInputs = [
     automoc4
     cmake
+    makeWrapper
     perl
     pkgconfig
   ];
@@ -24,6 +27,10 @@ kdeApp {
     kdelibs
     kdepimlibs
   ];
+  postInstall = ''
+    wrapProgram "$out/bin/kgpg" \
+        --prefix PATH : "${gnupg}/bin"
+  '';
   meta = {
     license = [ lib.licenses.gpl2 ];
     maintainers = [ lib.maintainers.ttuegel ];