OpenResty version exposed when hitting /50x resource

[jmdacruz]

Summary

When sending an request to the /50x of the server, a 404 error is returned with the version of OpenResty. The expectation is that Kong's error handler also captures this, instead of exposing information about OpenResty and it's version. The information is not only provided in the HTML body, but also on the Server header (which typically has Kong's version number instead)

Steps To Reproduce

1. Call http://{KONG_HOST}:{KONG_PORT}/50x

Additional Details & Logs

• Kong version (0.8.3)
• Kong configuration (Default configuration file, regardless on what APIs are configured if any)
• Ubuntu 14.04

[subnetmarco]

Possibly related to the same root problem of #1552.