Add QQuickMatrix4x4, a way to specify a matrix transform in QML.

Add QQuickMatrix4x4, a way to specify a matrix transform in QML.

Add QQuickMatrix4x4 which makes it possible to specify a 4x4
matrix tranformation directly in QML instead of decomposing the
transformation into rotation, scale etc. It does NOT replace anything,
just adds a new way of specifying a tranformation of an Item.

Change-Id: I1b123778d1d458dfe4314cdb4f0fc99fd8a4c86a
Reviewed-by: Alan Alpert <aalpert@blackberry.com>
Reviewed-by: Robin Burchell <robin+qt@viroteck.net>
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>