fix NEUMeshIO.read() for empty lines and 3_8 cells
fix NEUMeshIO.read() for empty lines and 3_8 cells

sfepy/sfepy,vlukes/sfepy,lokik/sfepy,vlukes/sfepy,sfepy/sfepy,lokik/sfepy,rc/sfepy,rc/sfepy,BubuLK/sfepy,rc/sfepy,BubuLK/sfepy,vlukes/sfepy,lokik/sfepy,sfepy/sfepy,lokik/sfepy,BubuLK/sfepy