Improve performange benchmark

[fomkin]

Currently there is abandoned module named performange-benchmark. It can massively replay scenarios recorded with Korolev.setDebugEnabled(true) It is may be powerful tool if someone take to maintain it.

What I see we can do just now:

1. Documentation.
2. Fix bugs with connections.
3. Export delay to config.
4. Find why delay added to latency of the first request/response.

In the future we can make GUI tool which allows to record scenarios and show pretty charts.