Fix for slow tcp connect in non blocking mode

[tdev]

Hotfix for nonblocking, slow TCP connections not returning instantly. If the connect() takes too long, it will return WSAEALREADY, which when linked incorrectly, return WSAINVAL instead. This will destroy the connection.

Quote from: https://msdn.microsoft.com/en-us/library/windows/desktop/ms737625(v=vs.85).aspx

WSAEALREADY: A nonblocking connect call is in progress on the specified socket.
Note In order to preserve backward compatibility, this error is reported as WSAEINVAL to Windows
Sockets 1.1 applications that link to either Winsock.dll or Wsock32.dll."

The attached patch converts any WSAINVAL to WSAEALREADY. This has the problem, that if you really have invalid arguments (call connect on a listening socket) it will not fatally fail anymore.

[ewestbrook]

Can this be done without breaking the listening socket error case?

In other words, can we test whether it's a listening socket and only convert WSAINVAL to WSAEALREADY when it's not?

If we can't test for that, should we make note of it when socket_listen is called?