fix doc
fix doc

fix #656

ephes/gunicorn,harrisonfeng/gunicorn,wong2/gunicorn,MrKiven/gunicorn,jamesblunt/gunicorn,mvaled/gunicorn,jamesblunt/gunicorn,gtrdotmcs/gunicorn,wong2/gunicorn,prezi/gunicorn,WSDC-NITWarangal/gunicorn,keakon/gunicorn,prezi/gunicorn,1stvamp/gunicorn,jamesblunt/gunicorn,beni55/gunicorn,zhoucen/gunicorn,ccl0326/gunicorn,malept/gunicorn,z-fork/gunicorn,1stvamp/gunicorn,malept/gunicorn,gtrdotmcs/gunicorn,wong2/gunicorn,zhoucen/gunicorn,tempbottle/gunicorn,ccl0326/gunicorn,GitHublong/gunicorn,malept/gunicorn,prezi/gunicorn,zhoucen/gunicorn,ccl0326/gunicorn,tejasmanohar/gunicorn,1stvamp/gunicorn,mvaled/gunicorn,mvaled/gunicorn,gtrdotmcs/gunicorn,elelianghh/gunicorn