clean up setup.py, and also try to recover from bad pyrex compiled source by cleaning up pyrex files and retrying build
clean up setup.py, and also try to recover from bad pyrex compiled source
by cleaning up pyrex files and retrying build

RitwikGupta/pygr,theoryno3/pygr,ctb/pygr,GenDataPro/pygr,ctb/pygr,ctb/pygr,cjlee112/pygr,GenDataPro/pygr,theoryno3/pygr,theoryno3/pygr,GenDataPro/pygr,ctb/pygr,cjlee112/pygr,cjlee112/pygr,RitwikGupta/pygr,cjlee112/pygr,RitwikGupta/pygr,ctb/pygr