`ktor` performance with hello world with 6 client ...

# ktor

[rocketraman]

ktor performance with hello world with 6 client threads and 200 connections:
* jetty backend: 83k req/s, avg latency 4.54 ms, std dev 6.10 ms, 99% of requests in 24.8 ms
* netty backend: 32k req/s, avg latency 46.3 ms, std dev 109 ms, 99% of requests in 531 ms