no_gc: add documentation describing the feature
no_gc: add documentation describing the feature

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