Position sensitive tube scaling

[NickDraper]

Position sensitive detectors in tubes are unfortunately not uniform in the detectable regions. We need to be able to adjust the instrument definition based on a calibration file. This includes translating detectors (which we can already do) as well as stretching detectors along the axis of the tube (which I beleive openGL supports but we do not at the moment).[[BR]]

ObjectComponent would need to store the scaling factors in all 3 axes, and the visualization would need to apply them. Also object methods such as solid angle will need to apply these (possibly pass this to Ron once factors are in place)

[NickDraper]

This issue was originally trac ticket 358