[arch-multilib] New packages: wine-staging and more

Hi, As wine-staging being integrated into WineHQ as an official part [1], I would like to provide a package for it. I have discussed this with our current Wine maintainers and we have come to an agreement. My plan is to upload the lib32-libva tree first, and then wine-staging with {lib32-,}attr (Windows ACL), {lib32-,}libva (GPU decoding), {lib32-,}libpulse (PulseAudio driver) enabled. I'll discuss with Alucryd with the lib32-gtk3 tree later. Thank you! [1] https://wine-staging.com/news/2015-09-25-winehq-integration.html -- Regards, Felix Yan