Add Dired+ and customize it slightly

mode-customizations/dired-mode.el

@@ -1,6 +1,8 @@
 (defun customizations-for-dired-mode ()
   (interactive)
+  (linum-mode t)
   (define-key dired-mode-map (kbd "c") 'dired-create-directory)
-)
+  (when (require 'dired+ nil 'noerror)
+    (toggle-diredp-find-file-reuse-dir 1)))
 
 (add-hook 'dired-mode-hook 'customizations-for-dired-mode)

packages.el

@@ -32,6 +32,7 @@
     browse-kill-ring
     buffer-move
     coffee-mode
+    dired+
     feature-mode
     fill-column-indicator
     flymake-coffee