Remove the C functions to request OUYA price list. The interface wasn't done well, and they are not needed anyway
The Java price list request functions are used when making a purchase, but for now we don't need to clutter things
up with price requests that don't actually do anything
Add support for OUYA Discover Storereceipt checking.
Receipts only exist for "entitlement" products, not for "consumable" products