Use nlinum instead of linum

Supposedly it's faster. Also - use the actual global mode. :-)

CHANGELOG.md

@@ -4,7 +4,7 @@
 
 ### New features
 
-* Enable `linum-mode` by default. Can be disabled by setting `prelude-minimalistic-ui` to `nil`.
+* Enable `nlinum-mode` by default. Can be disabled by setting `prelude-minimalistic-ui` to `nil`.
 
 ### Changes
 

core/prelude-packages.el

@@ -75,6 +75,7 @@
     projectile
     magit
     move-text
+    nlinum
     operate-on-number
     smartparens
     smartrep

core/prelude-ui.el

@@ -61,7 +61,9 @@
 
 ;; show line numbers at the beginning of each line
 (unless prelude-minimalistic-ui
-  (linum-mode))
+  ;; there's a built-in linum-mode, but we're using
+  ;; nlinum-mode, as it's supposedly faster
+  (global-nlinum-mode t))
 
 ;; enable y/n answers
 (fset 'yes-or-no-p 'y-or-n-p)