Add Payment Gateway for Floreant POS

I need some modifications to the open source FloreantPOS. We need a processor option of our own that we can select to setup credentials, ip, and port of proccessing gateway API. We shall provide the API documentation for our gateway to form your API requests. Process is like this: Press Credit Card "Pay", and it contacts the gateway through a POST request. If approved it should get a token to store for the order if it is approved, if declined, it should prompt "Declined" and does not apply payment to the balance so the ticket may either be closed, or another payment may be applied to resolve the balance due. Additionally, we need a way to allow users to adjust their payments to add a tip by passing the token back to the gateway through post request. Finally we need a way to adjust, or delete payments from open orders, as well as create a refund. If you do well, we have other needs as well to be fulfilled immediately. Please take a look at the existing features of the software by installing and playing around with it, you'll be able to re-use a lot of existing core functionality. Please do this before bidding if you are not familiar with Floreant POS. Thanks.