Add parallel rendering and game update support

[ensisoft]

If the renderer runs frame late it should be possible to run game update and renderer render in parallel in different threads.

For Frame N

• The update for frame N+1is kicked off
• Renderer produces frame based on frame N-1 data.
• Get the result of the update thread and apply state changes on the renderer to prepare it for the next frame

For frame N+1 The update for frame N+2 is kicked off Renderer produces frame based on frame N-+1 data.

• etc