unv2ccx v2.0.0

Refactored file structure to be compared with another my converter - ccx2paraview.
Tests added. Readme updated.

unv2ccx v1.1

Fixed bug with empty sets in Salome.
Test models included in the distribution.

unv2ccx v1.0

Refactored Joël's Cugnoni UNV converter.
Adopted to Python 3.
Now it supports beams.
Tested in CalculiX GraphiX and CalculiX CAE.