Circular Arc not correctly represented when converting to VTK

[whliu91]

when a circular arc is converted to VTK mesh
now all arc are represented as minor arc
in IGES, this should be determined by the start and end point of an arc which is always counter-clockwise

in pyiges/geometry.py, line 634 (CircularArc.to_vtk())

There should be an extra bool passed to pv.CircularArc to indicate whether the arc is negative (major or minor) or not, determined by the sequence of the two points

pyvista ref (https://docs.pyvista.org/version/stable/api/utilities/_autosummary/pyvista.CircularArc.html)