added online recharge method to Recharge model
added new filter isRechargeable
added new file OnlineRechargeController.php
fixed: enc_key field name.
added direcpay methods.
added new constants

added new constants for enabled/disabled
Added new Model for OnlinePayments

added new model OnlinePayment.php with a new method to get all active
payment gateways.
added new migration: online transactions
added new migration: direcpay transactions
added new model: DirecpayTransactions.php