Add GitHub Actions for MSVC and MSYS2

[scribam]

This will built Spout2 for the following configurations and will provide feedback about compilation status:

• MSVC
  • Win32
  • x64
  • ARM64
• MSYS2
  • mingw32
  • mingw64
  • ucrt64
  • clang64

[leadedge]

Thanks for your work with this. I have looked into GitHub actions before and don't want to include it at this stage. I don't have ARM or MSYS2 set up either. I will look at it when I have time to do it thoroughly.

[leadedge]

Thanks again for your work on this. I regret that I can't include this in the repository stage. I have saved the two yml files and will follow up when I can devote the time to investigation and testing.