remove conn from the heap in conn_close
remove conn from the heap in conn_close

fixes #70

cgvarela/beanstalkd,r3jack/beanstalkd,naderman/beanstalkd,wfxiang08/beanstalkd,justintung/beanstalkd,yetone/beanstalkd,pinguo-xudianyang/beanstalkd,orangeholic/beanstalkd,CompendiumSoftware/beanstalkd,kr/beanstalkd,aidaima/beanstalkd,CompendiumSoftware/beanstalkd,bmhatfield/beanstalkd,ifduyue/beanstalkd,cgvarela/beanstalkd,LomoX-Offical/beanstalkd-win,mickeyouyou/beanstalkd,r3jack/beanstalkd,mobliyishengyuan/beanstalkd,Qihoo360/beanstalkd-win,wyzssw/beanstalkd,potatosalad/beanstalkd,naderman/beanstalkd,JensRantil/beanstalkd,wyzssw/beanstalkd,Qihoo360/beanstalkd-win,PhillipMwaniki/beanstalkd,diditaxi/beanstalkd,diditaxi/beanstalkd,justintung/beanstalkd,mickeyouyou/beanstalkd,lzpfmh/beanstalkd,davies/beanstalkd,JensRantil/beanstalkd,ifduyue/beanstalkd,qbdsoft/beanstalkd,aidaima/beanstalkd,naderman/beanstalkd,orangeholic/beanstalkd,wfxiang08/beanstalkd,handautsav/beanstalkd,handautsav/beanstalkd,lzpfmh/beanstalkd,qbdsoft/beanstalkd,tdg5/beanstalkd,mobliyishengyuan/beanstalkd,tdg5/beanstalkd,kr/beanstalkd,bmhatfield/beanstalkd,davies/beanstalkd,PhillipMwaniki/beanstalkd,LomoX-Offical/beanstalkd-win,potatosalad/beanstalkd,amyvmiwei/beanstalkd,amyvmiwei/beanstalkd,pinguo-xudianyang/beanstalkd,yetone/beanstalkd