pointer change depending the mode

[lpatiny]

This issue is related to:

• Shift key #2708

Currently we are never sure what will be done when we press drag release an horizontal line in the Datum1D or Datum2D.

I would suggest to change the shape of the pointer depending the action that is done.

If it will be a zoom 1D:

If it will be a zoom 2D:

If it will be an action 1D or 2D and will add something:

In the case of the action 2D zoom, we do nothing so we don't change the pointer.

In the case of the action 1D zoom we measure a distance and we could use this pointer: