Fork tcp server

This should be the fork tcp server, as discussed. If I still missed something let me know.

I put the amount of client connections in the test a little lower, used a replicateM_ 100 instead of 10000. The reason is that when we were doing that in three different tests (so basically 30k connections in one test run) we started running we started running into EADDRNOTAVAIL error upon connecting. This is due to the fact that those connections are still in TIME_WAIT and the sockets cannot be reused yet. We got this intermittently, so the only thing we could really do was make less client connections during the test runs.