Setup use-package

I like my emacs configuration to be managable in git installing everything on first start, as I migrated away from my home grown install and package manage to use-package I wanted to keep this nicety, so I need to make sure use-package gets installed if it isn’t already present.

;; setup use-package, if we don't have it, install it
(require 'use-package nil t)

(unless (featurep 'use-package)
  (package-refresh-contents)
  (package-install 'use-package)
  (require 'use-package))