don't include winsock2.h in public headers

[ligfx]

Windows headers have a tendency to pollute the global namespace and can cause issues with code that's not expecting it. enet should be a friendly neighbor and not expose Windows headers to end-users :)

[ligfx]

@lsalzman Any thoughts on this?

[lsalzman]

This won't work because the ENET_SOCKETSET_* and the ENET_HOST_TO_NET/ENET_NET_TO_HOST macros require winsock, and may be used as part of ENet's API.

[ligfx]

Dang, I didn't see those. Would you be open to another solution like, forward-declaring the SOCKET/ENetSocket type in the types.h header?

My use-case is I want to keep Windows headers out of my code headers (so they don't propagate), but still be able to use ENet directly in member variables or for function arguments.

[lsalzman]

I'll work something out with a define you can use before including to stop winsock.