Does not respond to window resizing

[rcarmo]

Might be a Wayland thing, but under Fedora the meshview window does not handle resizing correctly (the viewport remains stuck to the bottom corner, without scaling).

[KnIfER]

simple fix :

	// resize
	window.SetFramebufferSizeCallback(func(window *glfw.Window, w, h int) {
		gl.Viewport(0, 0, int32(w), int32(h))
		render()
	})