update Facets for empty facet groups
update Facets for empty facet groups

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