[PATCHES] Enable faster proxy response on low-latency links

Due to SLAs with our Tier-1 Carriers, we require support for a higher precision response window and a reduced proxy request timeout to be able to configure sub-second proxy response times.

We need to override response window for some Tier-1 carrier clients so the proxy server fails over to next home server faster to satisfy required response times of their tighter SLAs.

Sometimes a given sgsn has a very short-lived response time problem which doesn't deserve putting the home server into the zombie mode, so we'd like to configure tolerance to a certain amount of response 
window misses, which "max_response_timeouts" allows us to do.