msvc/winsock2 functions

[Peter Kümmel]

I've added the patched CheckTypeSize.cmake file
to cmake/modules which we should remove when there
is a new cmake release.

The configure process now finds some importand stuff

#define HAVE_STRUCT_ADDRINFO 1
#define HAVE_STRUCT_SOCKADDR_IN6 1
#define   HAVE_INET_PTON 1
#define   HAVE_INET_NTOP 1

but checks for

#define HAVE_GETHOSTNAME 1
#define HAVE_GETNAMEINFO 1

still fail, so I've added the macros to sys/socket.h,
because when including Ws2tcpip.h it's 100% sure that
they exist.
But we could also change config.h.cmake and
ConfigureChecks.cmake.

kdecore/netsupp_win32.cpp is now obsolete,
we could remove it.

Cheers,
Peter