Logger ~> Stevenson and don't inherit from Ruby Logger. #1106.

lib/jekyll.rb

@@ -28,7 +28,7 @@ require 'colorator'
 
 # internal requires
 require 'jekyll/core_ext'
-require 'jekyll/logger'
+require 'jekyll/stevenson'
 require 'jekyll/deprecator'
 require 'jekyll/configuration'
 require 'jekyll/site'

lib/jekyll/stevenson.rb

@@ -1,7 +1,7 @@
 require 'logger'
 
 module Jekyll
-  class Stevenson < Logger
+  class Stevenson
     # Public: Print a jekyll message to stdout
     #
     # topic - the topic of the message, e.g. "Configuration file", "Deprecation", etc.