Bug at the upper domain limit for unclamped splines (geomdl and Native implementations)

Created by: rendetto

I'm reporting the strange behavior of the unclamped splines mentioned in https://github.com/nortikin/sverchok/issues/4469 It is still present for Native and geomdl implementations with the most recent Sverchok master.

The setup is the same as used in https://github.com/nortikin/sverchok/issues/4469 (a constructed closed unclamped /periodic/ spline using wrapped control points - a convenient method for constructing arbitrary smoothly closed curves) The problem is present when taking a segment from a spline and the end (TMax) of this segment is exactly at the upper domain limit (which is 1.0 in this particular example)

I found that reverting to an earlier version of Sverchok (32f8f367) this problem is not present for both Native and geomdl. I run this early version of Sverchok under blender-2.90.0-windows64 and also aligned it to the corresponding Sverchok-extra for the time being. I also used the latest geomdl (v5.3.1) due to #3521 (closed) and https://github.com/orbingol/NURBS-Python/issues/115

As with other similar issues I got, there is a workaround that could "solve" the issue by using a value of 0.99999 instead of 1.0