Added a new skeleton file for glfw3 with 2 windows.
Find which monitor is (likely) the Oculus and place the second window on it. For some reason, it disappears when the first window is clicked on.
Call app callbacks only on appropriate window.
Refactor: extract function to find Oculus.
Add a SetPosition to move the non-fullscreen window onto the second monitor. Does not take title bar and border into account.