Instead of LibGUI and WindowServer building their own copies of the drawing
and graphics code, let's it in a separate LibDraw library.
This avoids building the code twice, and will encourage better separation
of concerns. :^)
Currently the two available input types are:
- GMessageBox::InputType::OK (default)
- GMessageBox::InputType::OKCancel
Based on your choice, GMessageBox::exec() will return ExecOK or ExecCancel.
