added writing planes in Type 108 not like BSplines
pcurves for planes not writing
add parameter for choice between writing planes in BSplines and Planes
0022820: OCCT IGES writer loses plane information
pcurves were prohibited also for BRep mode
Adding test case for this fix
Writing and reading tabulated cylinders in IGES were changed in accordance of Type 122 (parametrization [0,1]x[0,1]
some cosmetic changes
Adding test cases for this fix