CI: added github actions for build and for publishing the docs

[mgerhardy]

Added github actions for building sdl for the three major systems (linux, windows and osx)

the build currently fails for windows. There is some unresolved symbol - it already works for linux and macosx.

  SDL_xinputhaptic.c
  Generating Code...
     Creating library D:/a/SDL/SDL/build/Debug/SDL2d.lib and object D:/a/SDL/SDL/build/Debug/SDL2d.exp
SDL_hidapijoystick.obj : error LNK2019: unresolved external symbol close referenced in function HIDAPI_IsEquivalentToDevice [D:\a\SDL\SDL\build\SDL2.vcxproj]
D:\a\SDL\SDL\build\Debug\SDL2d.dll : fatal error LNK1120: 1 unresolved externals [D:\a\SDL\SDL\build\SDL2.vcxproj]
  Building Custom Rule D:/a/SDL/SDL/CMakeLists.txt
  SDL.c

I'm using cmake for the build at the moment. If there is interest in e.g. configure && make let me know.

Also included is a build job to publish the markdown from docs/ to github pages. See the following screenshot. I would also opt-in to cleanup the markdown... just let me know if this is desired. This is just published for the main branch. Should be available on https://libsdl-org.github.io/sdl/

[slouken]

Yes, if you want to clean up the docs for markdown, that would be great.

Thanks!

[mgerhardy]

It looks like github actions are not active for this project

[slouken]

I just enabled them, thanks!

[mgerhardy]

There is still a problem about no permissions for using external actions. Is that on purpose or by accident?