Pending purchase status should not result in entitlement

[kanetik]

Looking at the code here, it appears that if the purchase state is Pending, the customer is granted entitlement to the purchased item. However, per Google's documentation, that is the wrong way to handle Pending state. This would enable people to "purchase" the item without ever paying for it.

I think a good interim solution, so that current users of this library don't have a breaking change, would be a configuration setting that allows a dev to opt into the Google-approved model of handling Pending purchases.

[coderGtm]

I highly anticipate this vital addition. This librarys looks very good but some polishing is required. I am ready to contribute code, but I'd need some background from the maintainers about how and where to go for preventing entitlement in case of pending purchases