Fix msvc build

[xkbeyer]

Fixes to build evoke w/ VS 2019. Mainly:

• Get sha512 working on WIN32
• Added vcpkg openssl (done locally, not shure if that works on CI machine).
• Fix a crash while renaming the file evoke.db

[dascandy]

Thanks! Most of these are general fixes actually, I only see a Windows-specific #define in the cmakelists.