fix create_bnf() for numbers in identifiers
fix create_bnf() for numbers in identifiers

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