- wget is not installed by default on fedora 23.  Use curl instead
   since it is always available on recent Fedora.

 - The repo url for cockpit resulted in an http redirect message being
   saved as the repo file which broke deployment.  Update the url to
   url that was redirected to and ensure that future redirects will be
   handled correctly.

 - The main Fedora 23 repo includes salt packages, and there is no
   salt repo for 23.  The salt bootstrap still creates a repo file for
   a nonexistent repo, though, and this change removes it to avoid
   having dnf report an error on every update.