cython: update setup.py for mappings.pyx, reuse _fmfield library
cython: update setup.py for mappings.pyx, reuse _fmfield library

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