[PyQt] Fixes for itemview examples

[Hans-Peter Jansen]

On Mittwoch, 5. April 2017 00:22:31 Hans-Peter Jansen wrote:
> Hi Phil,
> 
> I've noticed a few glitches in the charts example.
> With the patch applied:
>  * it is able to load chart files
>  * selecting the pie don't crash
>  * saving files is successful

BTW, shouldn't QPainterPath.toFillPolygon() be callable without any arguments, 
using the QMatrix() overload internally? [see line 215 in chart.py]

Pete