(add-to-list 'auto-mode-alist '("\\.yml$" . yaml-mode))
(add-to-list 'auto-mode-alist '("\\.yaml$" . yaml-mode))
(add-to-list 'auto-mode-alist '("\\.yml\\.example$" . yaml-mode))

(add-hook 'yaml-mode-hook
          '(lambda ()
             (fci-mode)
             (linum-mode t)
             (define-key yaml-mode-map (kbd "RET") 'newline-and-indent)))