shell redirection fixes and directory creation

* Create /etc/chef-server if it doesn't exist.
  Ideally this should be our job, but it works.
* Use >/dev/null 2>&1 for redirection of stdout and stderr.
  &> is a bashism and doesn't work with posix shells (dash)
  >/dev/null 2>/dev/null works too.
  2>&1 >/dev/null <-- does not correctly redirect stderr