Add check for too small distances during edges reordering
Fix writing TrimmedSurface (Type 144).
Fix checking for too small distances between loops of edges during edge's reordering.
Add checking for too small BSpline segments during reading and writing IGES.
Fix wire splitting by adding checking that vertexes same not only in 3d, but in 2d too.
use tolerance of vertexes recomputed through resolution surface, not 2d curves.
Adding test case for this fix
Modified test case bugs iges bug23746 and cases in group de according to new reference data
Parameter to write offset curves like b-splines was added
Change function, which convert offset curves to b-splines
Added test command "test_offset"
Added test cases bugs/xde/bug23771_1 bug23771_2
