qxt: url fix

updated to the correct url for downloading the libqxt tar.gz file

pkgs/development/libraries/qxt/default.nix

···
   version = "0.6.2";
   
   src = fetchzip {
-    url = "http://dev.libqxt.org/libqxt/get/v${version}.tar.gz";
+    url = "https://bitbucket.org/libqxt/libqxt/get/v${version}.tar.gz";
     sha256 = "0zmqfn0h8cpky7wgaaxlfh0l89r9r0isi87587kaicyap7a6kxwz";
   };
 
···
       Development Frameworks, Nokia.
     '';
     license = stdenv.lib.licenses.gpl2;
+    platforms = stdenv.lib.platforms.linux;
     maintainers = with stdenv.lib.maintainers; [ forkk ];
   };
 }