Revert CMasternodePayments::IsTransactionValid to the logic before the recent refactorings (#2237)
Revert CMasternodePayments::IsTransactionValid to the logic before the recent refactorings (#2237)

partially reverts #2216 
ivansib/sibcoin,ivansib/sibcoin,ivansib/sibcoin,ivansib/sibcoin,ivansib/sibcoin,ivansib/sibcoin