Generalize --behavior-error-warmup

[nikhilm]

For example, I'm using websockets for a protocol, and I want the first few (TCP backend) packets to go through so that server and client finish their application level handshake. But after that I want the hang behaviour to kick in and stall all further communication.

Maybe just --behavior-warmup=10 and the behaviour kicks in after 10 reads or something?

[almet]

Sounds good yep, "Just proxy these first X packets and then start to do what you want".