Final Callback #7

This is not an issue as much as feature request, and i really don't know where else to put it, but i was wondering whether it would be a good idea to have a universal final callback after all the scraping is done.

For example, if i am hitting 20 urls, there is a callback for every hit, but what i want to close a db connection at the end of all the 20 hits and data manipulation. Thought it might be helpful at some point.

Thanks in advance