Added gateway name as a class to the payment type div to allow for greater styling control.
Wrapped the gateway name display in a span with class for added styling possibilities.
Remove inline styles from custom gateway image.
Don't wrap payment gateway display name in a span if it's empty.
_wpsc_filter_merchant_v2_get_gateway_list() code documentation and formatting.
Merge pull request #819 from benhuson/_bh_payment_types_checkout_2

PR for Styling enhancements for payment type display at checkout (rebased)