|SOURCE|
[Renderer::Window]
* Added an Update member function
Merge branch 'window_manager' into unstable
|SOURCE|
[Arithmetic::Matrix4x4]
* Changed the member function to retrieve the raw sixteen floating-point
  numbers to accept a pointer to the array, which is assumed to be initialised
[Renderer::RenderTypes]
* Added more ZED_RENDERER_BACKEND values
[Renderer::Renderer]
* Added a member function to retrieve the back-end renderer
[Linux::Renderer::LinuxRendererOGL3]
* BackEnd member function returns the correct back-end value