V1.1 - Swimming and Competition Beta + general fixes + 50% discount for 24h

This "beta" is on the main branch, as the main fitness also has improvements alongside with the beta features. So there is no separate "beta" branch, just so you're aware of that.

Swimming and competing over a cube has now been implemented for beta testing. While both produce interesting results already, competition over a cube between two creatures especially needs tweaking. Be aware that that swimmers and competition fitness creatures will be abusing physics a lot as I haven't put in a lot of restrictions yet. Especially swimmers like to grow to gigantic sizes to cheat the system, but I have already put in place SOME restrictions on it. They were infuriatingly hopeless prior to this. In addition, 50% discount for 24 hours to commemorate this release ^^