So now, when currentGame.gamePlay is set to GAMEPLAY_ONPON:
- You start with 50 shield, and never gain any increased capacity.
- You can't charge the charge cannon and shoot at the same time; if
you shoot the plasma gun, the charge cannon shoots as well (as if
you had released the charge key).
I didn't add in the feature to keep the view from slowing you down,
because the method I used was imperfect anyway.