Update some MELPA references

Author: Bozhidar Batsov

cider.el

@@ -34,15 +34,15 @@
 
 ;;; Installation:
 
-;; Available as a package in marmalade-repo.org and melpa.milkbox.net.
+;; Available as a package in marmalade-repo.org and melpa.org
 
 ;; (add-to-list 'package-archives
 ;;              '("marmalade" . "http://marmalade-repo.org/packages/"))
 ;;
 ;; or
 ;;
 ;; (add-to-list 'package-archives
-;;              '("melpa" . "http://melpa.milkbox.net/packages/") t)
+;;              '("melpa" . "http://melpa.org/packages/") t)
 ;;
 ;; M-x package-install cider