[PyKDE] convertSubClass() -- I introduced a bug :-(

[Dave Cuthbert]

Phil Thompson wrote:
> Just for stuff in QCanvas, *not* "and below".

I gave a bad example.  I meant "and anything *in the qcanvas module* 
that's below QCanvas" -- which is nothing.

QTableItem's subclass converter is clearly handling QCheckTableItem and 
QComboTableItem.

> Overlaying implies replacing - it's supplementing existing convertors.

Ah, yes, that's a better description.  I had already rejected "overload" 
and "override," and my mind was stuck searching for over-something.