fixing cmake build on windows

[crusader-mike]

I've got cmake build to work on Windows x64. Notes:

• tidied up cmake files a bit
• fixed one problem where SOCKET was truncated to int; there is another one (see what happens to handle returned by create_socket()), but it has to be fixed another time
• there are other warnings that need to be addressed at some point, but they seem to be minor
• dll version info is generated properly
• with this change it is trivial to add libnfs to vcpkg. See libnfs.zip

[crusader-mike]

@sahlberg Did I just managed to sneak in last minute fix before you merged it in or you were waiting for me to notice and fix a "missing exports" problem? :-)

[sahlberg]

This is the last commit I have from you : commit 9d5427b Author: crusader-mike <crusader.mike@gmail.com> Date: Wed Oct 9 17:08:10 2019 -0500 fixed few MSVC warnings; fixed missing exports Do I need additional ones? if so, can you send a pull request for them>

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On Thu, Oct 10, 2019 at 8:32 AM crusader-mike ***@***.***> wrote: @sahlberg <https://github.com/sahlberg> Did I just managed to sneak in last minute fix before you merged it in or you were waiting for me to notice and fix a "missing exports" problem? :-) — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#297?email_source=notifications&email_token=AADY3EEAEHGL3OTY236DE23QNZLWVA5CNFSM4IWSUVTKYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEAZU4UI#issuecomment-540233297>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AADY3EEVLQ77DRODQZLAKSTQNZLWVANCNFSM4IWSUVTA> .

[crusader-mike]

No, I pushed last commit (9d5427b fix for missing exports) literally a minute before you merged in the change. It looked like I managed to squeeze that fix right before you pressed "merge" button. Quite possible you didn't see new change (if I checked it in after you looked got github page, but before you pressed merge button) -- in this case it would be a github bug.

I just found this thought humorous...