Decouple TuxMath's rendering system and simulation system

completed by: Jakub Śpiewak

mentors: sids.aquarius, Deepak

Decouple TuxMath's (2 tasks - one for Comet Game, one for Factoroids) "rendering" system and simulation system. As mentioned in one of the previous tasks, the game currently runs at 15 FPS, for both simulation and rendering.