Don't let multiple pace-done classes get appended. Closes CodeByZach#97.

Author: Zack Bloom

pace.coffee

@@ -200,7 +200,7 @@ class Bar
       @el = document.createElement 'div'
       @el.className = "pace pace-active"
 
-      document.body.className = document.body.className.replace 'pace-done', ''
+      document.body.className = document.body.className.replace /pace-done/g, ''
       document.body.className += ' pace-running'
 
       @el.innerHTML = '''