added SIGINT handler
added SIGINT handler

shekyan/slowhttptest,drat/slowhttptest,rodrigoac/slowhttptest,michalkoczwara/slowhttptest,drat/slowhttptest,shekyan/slowhttptest,michalkoczwara/slowhttptest,erikdejonge/slowhttptest,blu3sh3ll/slowhttptest,blu3sh3ll/slowhttptest,rodrigoac/slowhttptest,erikdejonge/slowhttptest