Add more metadata to output

[maxmeyer]

Request

It would be helpful, if proxy check would output environment information - time, client ip. Additionally having the hostname resolved to it's ipv4 address would be very helpful.

Use case

Normally we would consider 10., 192. etc.-addresses to be "DIRECT" reachable, but in some cases we need to send non-local requests via a proxy server, e.g. there's a public domain www1.example.com mapped to a 10.-address.