new find_subclasses() utility function
new find_subclasses() utility function

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