Describes the "schema" for a an XML feed to "googlebase".



Note that this is only an "abstract schema" in the sense that



google base does not currently accept a "feed" in this format.



Instead, google base accepts feeds in a wide variety of "standard" XML



content feed formats (RSS2.0, Atom). The "item/entry" subelement of



a "RSS/Atom" feed corresponds to the "item" element defined below.



The sub elements of an item defined herein serve as the concrete



definition of the "googlebase defined extensions" to the Atom/RSS



schemas.