support extra parameters in Solver.process_conf()
support extra parameters in Solver.process_conf()

- marked by '*' name in _parameters solver attribute

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