Remove duplicate attr :annotation.

Author: ioquatix

lib/async/node.rb

@@ -123,10 +123,6 @@ def annotate(annotation)
 			end
 		end
 
-		def annotation
-			@annotation
-		end
-		
 		def description
 			@object_name ||= "#{self.class}:#{format '%#018x', object_id}#{@transient ? ' transient' : nil}"