Add empty header files for MSVC port

MSVC lacks many of the header files included by git-compat-util.h; add
blank header files for these instead of going ifdef crazy.
Signed-off-by: NMarius Storm-Olsen <mstormo@gmail.com>
Acked-by: NJohannes Sixt <j6t@kdbg.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

compat/vcbuild/include/arpa/inet.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/grp.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/inttypes.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/netdb.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/netinet/in.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/netinet/tcp.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/pwd.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/sys/ioctl.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/sys/param.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/sys/poll.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/sys/select.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/sys/socket.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/sys/time.h

+/* Intentionally empty file to support building git with MSVC */

compat/vcbuild/include/sys/wait.h

+/* Intentionally empty file to support building git with MSVC */