Get rid of marmalade dependency

This repo is often down which makes it very unreliable for a starter kit

README.md

@@ -67,8 +67,6 @@
                 - [Inferior REPL process](#inferior-repl-process)
                 - [Other R commands](#other-r-commands)
             - [rcirc](#rcirc)
-    - [Troubleshoot](#troubleshoot)
-        - [Marmalade repository is down](#marmalade-repository-is-down)
     - [TODO list](#todo-list)
 
 <!-- markdown-toc end -->
@@ -775,14 +773,6 @@ Send code to inferior process commands:
 `CTRL+j`          | next item in command history
 `CTRL+k`          | previous item in command history
 
-## Troubleshoot
-
-### Marmalade repository is down
-
-Unfortunately for now there is little you can do in `Spacemacs` if `marmalade`
-repository goes down and you need to install packages. Though there will be
-solutions in a future release of the contribution system.
-
 ## TODO list
 
 - Add support for [multiple-cursors][multiple-cursors] mode.

core/contribsys.el

@@ -2,7 +2,6 @@
 (require 'package)
 (setq package-archives '(("ELPA" . "http://tromey.com/elpa/")
                          ("gnu" . "http://elpa.gnu.org/packages/")
-                         ("marmalade" . "http://marmalade-repo.org/packages/")
                          ("melpa" . "http://melpa.milkbox.net/packages/")))
 (package-initialize)
 (setq warning-minimum-level :error)