FMSLogo Code

Remove false information from NETCONNECTON/NETACCEPTON.
The documentation said that you cannot "just" send from the sendready instruction callback list because it's only called if an earlier attempt to send failed. However, it's clearly documented below that it's also called at three other instances. I don't see why you couldn't send exclusively from sendready.

Fix a race between NETCONNECTON and NETSHUTDOWN wrt async DNS lookup

The fix is to store the handle from WSAAsyncGetHostByName so that it can be cancelled in NETSHUTDOWN if it hasn't yet completed. This fix was probably always needed, but it became more apparent recently as the network tests started to deadlock on a call to NETSHUTDOWN when all tests were run.

I expect that this fixes the real root cause of Bug #307.

Fix typo in comment: asynchronus -> asynchronous

Update call to WSAStartup to follow practices recommended on docs.microsoft.com
1) Version 2.2 is supported in-box since Windows XP. Previously, FMSLogo was requested 1.1, probably a legacy from the 16-bit windows machines that MSWLogo was written for.
2) The return value should be used without calling WSAGetLastError()

Refactoring: extract CServerNetworkConnection::AcceptNewConnection()
This was done to remove duplication of identical logic.

Refactoring: Stop passing a HWND as parameters in the network API.
This wasn't needed, since the only HWND is the main window.

Clear m_ConnectionIsWaitingToBeAccepted when NETACCEPTOFF is called.

Minor improvements:
* Add support for a "temporary redirect" response.
* Check for malformed HTTP Request message

Fix a problem where if a second connection was created to a NETACCEPTON server while it was already connected, then winsock would not raise any more FD_ACCEPT events and the server wouldn't be able to process any further connections.

The fix is to a set flag when NETACCEPTON is too busy to accept a second connection, then to later execute accept() once the first connection is closed.

Don't immediately return from AsyncSelect callback on error.

The important thing is to process the FD_CLOSE event even when it comes from a socket reset. Otherwise a NETACCEPTON server can get into a bad state where it no longer accepts new incoming connections.