Don't use hook_feedapi_after_refresh()

We've started using hook_feedapi_after_refresh() because historically we used flatstore (now data) module for dynamically allocating table space when refreshing a feed. This is not such a good idea in the first place, now we are allocating table space when mapping.

We could go back now to use the appropriate FeedAPI hook (hook_feedapi_item) for creating items. Before that, we need to clean up the 'map' invokation of FeedAPI Mapper 2.x which is sort of in limbo now as it is not fully node agnostic yet: #519378: Remaining 'node as feed item' related code .