Scadnano import does not take into account helix-specific position / rotation / etc.

[cgevans]

Scadnano imports take into account group position and orientation, but not helix position and orientation. This is important for scadnano designs that don't have a grid; in this case, it appears that the import uses a default grid and grid position for each helix.

In the attached file (extension renamed from .sc), for example, the helices are arranged in a curved fashion. c-small.txt