add cython_freeze to readme
add cython_freeze to readme

ChristopherHogan/cython,cython/cython,scoder/cython,scoder/cython,scoder/cython,cython/cython,da-woods/cython,da-woods/cython,fabianrost84/cython,c-blake/cython,ChristopherHogan/cython,fabianrost84/cython,ChristopherHogan/cython,c-blake/cython,scoder/cython,fabianrost84/cython,c-blake/cython,fabianrost84/cython,da-woods/cython,cython/cython,da-woods/cython,c-blake/cython,c-blake/cython,cython/cython,fabianrost84/cython