windows: Enable building Privoxy with OpenSSL

windows: Enable building Privoxy with OpenSSL

- openssl.c

I got random crashes when using openssl on windows; fixed with
  #include <openssl/applink.c>
I don't understand
  https://www.openssl.org/docs/faq.html
it seems to be applicable only to calling DLLs but even with
no DLLs involved that include also fixes the crashes that happen
when statically linking openssl

- project.h

pull in the required gunk for windows