Merge pull request #46 from github/runtime_header

Removes the X-Runtime header from ActionController::Benchmarking

actionpack/lib/action_controller/benchmarking.rb

@@ -87,7 +87,6 @@ def perform_action_with_benchmark
           log_message << " [#{complete_request_uri rescue "unknown"}]"
 
           logger.info(log_message)
-          response.headers["X-Runtime"] = "%.0f" % ms
         else
           perform_action_without_benchmark
         end