Edit camera is now controlled as in Qt 3D Studio:
ALT + left button orbits camera.
ALT + middle button pans camera.
ALT + right button zooms camera.
Wheel zooms camera.
Task-number: QDS-1206
Change-Id: Ia72644073d172b00483ceed8bcc5ffb8dce68741
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>
