Release 0.0.3

Fix render re-enable timing for scene transitions and save loading

Fix render re-enable timing for scene transitions and save loading

Move Game.Instance.EnableRendering() out of the unsafe scene-unload path.

Savegame loading can temporarily load the first scene of a level, then load
the actual saved scene, and finally unload the initially loaded scene while
the loading screen is still active. Re-enabling normal game rendering during
that unload caused the loading screen and RenderManager to use incompatible
buffers, which could crash saved-game loading.

Instead, re-enable rendering from safer load-task points:

- after normal scene changes have been queued
- after PlayState exit cleanup has waited for rendering to be disabled
- after the old PlayState is no longer the active state