Multiple format options for reviews, allows review date fetching
I've noticed that there's another PR that introduces the date field in the review methods by moving
store.reviews to XML.
Parsing XML is slower but gives access to the date field so I think the user should have the ability to chose their preferred format based on requirements.
This MR introduces the ability to use the XML RSS feed while fetching review data. I've added some tests for making sure that popular app returns the same reviews independently from the chosen format or parameters.
@LobeTia I have question about explicit_array = false. Would it not cause a trouble if there is just a single review?
Is this gonna be merged?