Windows: openssl installer doesn't auto-install anymore

[tracernz]

We pick up the latest version automaigcally since 9064d53... but the latest installer will not accept any flags to set install path and silent install. It's InnoSetup based. I'm not sure how to proceed other than sourcing from an alternate source (msys2 repo?).

[mlyle]

IMO it's not the end of the world if a user has to click through it for now.

[tracernz]

Well, we don't tell them the path to install to ;)