Mordernize code base with __dir__ and require_relative

example/server/server.rb

@@ -1,11 +1,9 @@
 require 'webrick'
 require 'rexml/document'
 
-DIR = File.expand_path(File.dirname(__FILE__))
-
-require DIR + '/../../lib/liquid'
-require DIR + '/liquid_servlet'
-require DIR + '/example_servlet'
+require_relative '../../lib/liquid'
+require_relative 'liquid_servlet'
+require_relative 'example_servlet'
 
 # Setup webrick
 server = WEBrick::HTTPServer.new( :Port => ARGV[1] || 3000 )