like Malloc, Realloc and especially Free conflict with already existing names
on some operating systems or other packages. That is reason enough to change
the names of the OpenSSL memory allocation macros to something that has a
better chance of being unique, like prepending them with OPENSSL_.
This change includes all the name changes needed throughout all C files.
without -debug option to mk1mf.pl. Change _export to is_export (_export is
a reserved word under VC++). Add yucky function prototype function pointer
casts. Sanitise the included files in crypto/x509v3.
Also changed ssleay.exe target to openssl.exe
