RenderMesh set to dirty on peer change

This allows the RenderMesh - MeshData link to be updated when the frontent
peer Mesh assigned to RenderMesh is updated.

Change-Id: I36c6beca551709e5f0f68e3bfe354bf7baa78885
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Quick3D independent library

In order to be able to have Qt3D work without dependencies to the Qml module,
a dedicated Quick3D library has been set up for that purpose. It offers a
QQuickWindow class which extends Qt3D::Window and allows to load a Qml source
file.

Examples have been updated to use QuickWindow.

Note: There are still dependencies to the Qml module in Qt3DCore and
Qt3DRenderer. This patch is a first step toward the removal of those. Follow
up commits will completely remove those dependencies.

Change-Id: I603eec8fb01b3706f648550b43b62356b0b4b4ac
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Quick3DTransform

Quick3D frontend element to create a Qt3DCore Transform element from Qml.
The QQmlListProperty was removed from Transform and transferred to
Quick3DTransform so that in a near future all Qml dependencies will be removed
from Qt3DCore.

More similar follow-up patches to follow.

Change-Id: I0154da986176da31d58738123a6b56f63ccaf32e
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Renamed QmlEntity to Quick3DEntity

To be consistent with the quick3d module name and other quick3d elements.

Change-Id: Iaed819e9690a5c516aaadad2b62ecc4f25332853
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>