hierarchic: raise error for surface mapping with hierarchical basis
hierarchic: raise error for surface mapping with hierarchical basis

- update Approximation.describe_geometry()

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