zettel.rb in jekyll-zettel-0.4.0

- old
+ new

@@ -35,5 +35,6 @@
 require 'jekyll/commands/zettel'
 require 'jekyll/zettel/references'
 require 'jekyll/zettel/reference'
 require 'jekyll/zettel/timeline'
 require 'jekyll/zettel/tags'
+require 'jekyll/zettel/zettelkasten'