Travis: Initiating build for commit 'a2f3959a8c3f730d871fbe0e3cc437a64ac98494' on branch 'master': refs #5958 add http error code 500 header in case of piwik errors.
Could we also add a call to error_log to log in the error.log ?
(we cannot use Log::debug or so as the logger may not be initialised yet)