The QtQuick examples should ideally have a more native look and feel.
Making them use controls from QtQuickControl will cause them to adapt to
the desktop style.
This patch replaces the previous Sliders from the 'shared' directory,
with Sliders from QtQuickControls2
Task-number: QTBUG-90880
Change-Id: I90521abf7059950521bc3d1a54994d2cca07259d
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>
Oliver Eftevaag