New .gitignore

Added new .gitignore from Robert.
Asset Additions

Added track pieces from Bob.
New player prefab with material and new scale.
Respawn checkpoints placed onto track.
Performance test scripts in place (HUD FPS script).
Updated Prefabs for the TRex and Diloph
Merge commit '6fadd184b0ee09612a411981149935fb7f3d3bb4'

Conflicts:
	.gitignore