File _service of Package emacs-snapshot

<services>
  <service name="tar_scm"><param name="url">git://git.savannah.gnu.org/emacs.git</param><param name="scm">git</param></service>
<service name="download_url"><param name="path">http://hydra.nixos.org/build/1446126/download/1/emacs-24.0.90.tar.gz</param><param name="host"></param></service></services>