With '%', non-ascii worked because the '%' automatically got promoted to
unicode. With format that doesn't happen, which led to encoding errors. This
fix goes back to using %, and adds a test to make sure non-ascii string values
work in iterdump.
Although there is not a regression in Python2, we make the same update here to
keep the code bases in sync.
(The fix for issue 9750 introduced a regression in Python 3 by sorting the row
objects returned by fetchall. But if a row_factory such as sqlite3.Row is
used, the rows may not be sortable (in Python3), which leads to an exception.
The sorting is still a nice idea, so the patch moves the sort into the sql.)
Fix and test by Peter Otten.