Add withSocketsDo for Windows.
Merge branch 'master' of https://github.com/overminder/punch-forward
Add transmission status logging.

Logging indicates that although the payload efficiency for the
input stream is Okay (80%-90%), the output stream suffers from extremely
bad efficiency (<1%-5%). Most of the bandwidths are occupied by the ACK-ECHO
packets.

A solution for it, just as what TCP does, is to use delayed ACK.