Software Público Brasileiro

MOD: Change logic for when to use coil without handle to mark the target

- Previously, coil without handle was used to mark the target only if
  object calibration had not been done yet. After object calibration
  was done, the variable polydata stored the coil mesh that was selected
  by the user when doing the calibration, and hence that coil mesh
  (typically containing the handle) was used to mark the target.

- Change the logic to follow these rules:

  * When the default coil is selected in object calibration, use the
    default coil with a handle to mark the coil location, and default
	coil without a handle to mark the target.

  * When object calibration is not yet done, use default coil without
    a handle to mark the target.

  * When a custom coil is selected in object calibration, use the custom
    coil to mark both the coil location and the target, regardless of if
    the mesh contains handle or not. This is done because otherwise the user
    would need to select two custom meshes, one that is used to mark the coil
    location and another for the target.