simplify eval_basis_transform() - remove eval_bf(), update assign_transform()
simplify eval_basis_transform() - remove eval_bf(), update assign_transform()

- fix(?) 3D

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