Axis helper shows up on top right corner of 3D edit view.
Clicking on axis helper arms zooms camera on that side of the selected
object.
Change-Id: Ibd81a933036f7965f825e3dc97ad7156da62e14c
Fixes: QDS-1205
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>
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>