fix doc/conf.py for numpydoc_path set to None
fix doc/conf.py for numpydoc_path set to None

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