windows support

[noah1510]

At the moment windows is not tested despite the large developer/user base.
Here are some steps to get basic windows support working.

• figure out how to install windows dependencies
• update Ci to also build for windows
• test meson windows build (should work out of the box)
• test cmake windows build (maybe also works out of the box)

[barcharcraz]

Things seem to compile fine on windows, I've made a vcpkg port. However shared builds don't work because you don't export any symbols.

[barcharcraz]

oh, I had to patch a single definition that wouldn't compile in msvc since msvc doesn't support compound literals in c++ mode.