This fix deals with selecting the right OpenGL headers based on operating system using the existing code in the shell library.
Merge branch 'hotfix/sfml2-opengl-includes' into stable
Merge branch 'hotfix/sfml2-opengl-includes'
Properly fix the Lua/check() macro collision
Merge branch 'hotfix/osx-lua-check-builtin-macro-collision-fix2'