cp2: stuck in upload timeout
Merge branch 'master' of https://github.com/fengjingchao/peer_server
Merge branch 'master' of https://github.com/fengjingchao/peer_server
be a little bit more aggressive when entering congestion avoidance
tune on timeouts.. add upbound for backoff
Merge pull request #11 from yifan-gu/master

check timeout for upload