Use SetFileCompletionNotificationModes when attaching.

[Berrysoft]

Some IO methods may success immediately. However, it will also issue a packet to IOCP. Now in #82 we've allowed success immediately in push, so it is possible to handle these methods, and disable the packet issue.

We can disable the inner event handle of file object as well. It may improve the performance a little.

Reference

https://learn.microsoft.com/en-US/troubleshoot/windows/win32/asynchronous-disk-io-synchronous

https://devblogs.microsoft.com/oldnewthing/20190719-00/?p=102722

https://devblogs.microsoft.com/oldnewthing/20200221-00/?p=103466

https://github.com/dotnet/corefx/pull/15141

[Berrysoft]

It seems that some IO futures return Ready on first call to Future::poll.

[Berrysoft]

SetFileCompletionNotificationModes is in OneCoreUAP, which means it could be used in UWP.

[Berrysoft]

There are some notes:

• This method doesn't work if the user doesn't use an IFS LSP. It seems still to be a problem in 2017. https://github.com/golang/go/issues/22149
• dotnet says that this method shouldn't be used in UWP. We need to confirm. Update: dotnet removed this limitation.
• Go only enables this for TCP sockets. The reason why not udp is removed; the reason why not file handle seems nonsense.

[Berrysoft]

LSP is deprecated. I think we can just ignore them at now.