Clean up linum configuration

Part of the configuration was in packages.el right after the require
call to linum+. It's now in appearance.el next to the related linum
settings.

appearance.el

@@ -31,6 +31,12 @@
 (setq linum+-smart-format " %%%dd ")
 (setq linum+-dynamic-format " %%%dd ")
 
+;; Linum+ resets linum-format to "smart" when it's loaded, hence we have to
+;; use a eval-after-load hook to set it to "dynamic".
+(eval-after-load "linum+"
+  '(progn
+     (setq linum-format 'dynamic)))
+
 ;; meaningful names for buffers with the same name
 (require 'uniquify)
 (setq uniquify-buffer-name-style 'forward)

packages.el

@@ -181,8 +181,7 @@
   (require 'undo-tree)
 
   ;; Load Linum+
-  (when (require 'linum+ nil 'noerror)
-    (setq linum-format 'dynamic))
+  (require 'linum+)
 
   ;; Load full-ack
   (require 'full-ack)