Unity 5.12 Fixes Ubuntu OpenGL Performance Problems

The Lightsmark frame-rate went up by 20% when moving from Unity 5.10 to Unity 5.12, but still Unity 2D led to superior results.

The Nexuiz results were rather odd with some problem taking place under Unity 2D, but for the standard Unity desktop there is still an improvement with the 5.12 release.

OpenArena 0.8.5 ran 28% faster with the trivial Unity 5.12 upgrade.