[Control Scheme Option] Prevent JC Grab while holding shield#1057

I have played with nair on air grab for all my time playing this game, but there is an issue with that which makes nair on parry strictly better : nair out of shield. When trying to get a nair oos, you cannot buffer the nair using grab since you will get a jump cancel grab, something that does not happen using nair on parry.

For that I propose a simple control scheme option : prevent jump cancel grab while holding shield. This option would let us air grab nair users do buffered full drift nair oos like air parry nair users. It would be the same kind of options as the recently introduced wavedash assist and supress dash attack.

I really like this idea. Personally made the swap to air parry + nair for this very reason.