Option to auto forward to checkout page when payment is completed.

[astupidmoose]

Right now the customer receives a confirmation of payment when using mycelium on the same page as the QR code is displayed.

Google Analytics does not mark this as a "successful order" as the customer usually exits from this point and does not click the continue back to account area.

My proposed fix is to simply forward the customer back to the checkout/success page once mycelium has received payment. This will then properly record the payment int google analytics