[Development] QList

[Philippe]

> . points are items
> . QPolygon is a sequential collection of points
> . QVector is a sequential collection of items
> ? QPolygon is-a QVector
> 
> which is a fallacy.

QPolygon needs not be a QVector
QPolygon can be a QVector
QPolygon can be a QList

...but *today*, QPolygon is "implemented as a QVector"
Hence from the OO common dialect, QPolygon is-a QVector

Philippe