optional payout address on the claim function

[significance]

So in each claim it automatically gets sent to a designated address (or if address(0), send to msg.sender)

credit: @mfw78

[0xCardiE]

This will then remove the option that anyone can run a claim, currently, anyone can, winner is selected but doesn't have anything to do with the caller of trx. This would need to be changed so that only the winner can be the caller and then he can change where he wants to send winnings.

[mfw78]

Or you can allow payee delegation on the StakeRegistry.