VS2013 has trouble with relative include paths for apps/openssl, so move
certhash_win/apps_win.c back to apps/openssl.
gmtime_r on mingw64 fails with negative time_t, override
gmtime_s fails all of the time unit tests, override
SHUT_RD/WR are defined in newer mingw64 headers, check before overriding
Note that 'perror' moves from stdio.h to stdlib.h, and 'rename' moves
from stdio.h to io.h. Also, standard C includes move from the compiler
to the Windows SDK, which changes the base path for the include files.
This moves the compatibility include files from include to
include/compat so we can use the awful MS C compiler
<../include/> trick to emulate the GNU #include_next extension.
This also removes a few old compat files we do not need anymore.
