Store a product to an OutputStream using ZIP.
Accumulates entire product the same as ObjectProductOutput, then onEndProduct
outputs a zip file containing "product.xml" as the first entry and all
product content as other entries.
Because the zip file is not written until after all content has been
"received", all product content may result in in-memory buffering. This is
not the case when dealing with File-backed products. If this is a concern,
users are encouraged to use the Xml Input and Output classes, which always
use streams and never buffer content.