Adding a property to set flicking velocity

This is about Flickable QML component.

Currently, the amount of scroll (i.e. velocity) can be set by changing maximumFlickVelocity property.
If you change maximumFlickVelocity to 10, 100, 1000.., the Flick velocity increases accordingly.

However, the velocity no longer seems to change over 10000.
That is, the result of setting 10000 and 10000000 look the same.

The property requested here enables the app to control the maximum of velocity