Update FlopGame.js

All Big Blind checkbox issues should be corrected with this version, when sitting out both check/fold and BBcheck is hidden, when sitting in BBCheck shows up and doesn't dissapear. Quite a few changes from last update, but I think it is Pretty solid. 

Also line 80, 81 is for check/fold issue still plan to work on later tonight.

Thanks let me know if all is well.