Add missing comment and check for nil EtcdClient
Add missing comment and check for nil EtcdClient

kelseyhightower/confd,elsonrodriguez/confd,karthequian/confd,tomdee/confd,kelseyhightower/confd,linearregression/confd,openedbox/confd,fritzy/confd,chendh521/confd,elbidigital/confd,layerhq/confd,Ropes/confd,agilemobiledev/confd,gautamk/confd,glerchundi/confd,beni55/confd,cvrabie/confd,Fitbit/confd,RichardKnop/confd,zytek/confd,bacongobbler/confd,philipsoutham/confd,shencan/confd,Lineberty/confd,zytek/confd,cloudnautique/confd,crunchywelch/confd,Flipkart/confd,karthequian/confd,RichardKnop/confd,crandles/confd,openedbox/confd,nevermosby/confd,alexnauda/confd,Flipkart/confd,elsonrodriguez/confd,rancher/confd,aledbf/confd,monder/confd,danesparza/confd,bacongobbler/confd,PrFalken/confd,chendh521/confd,deis/confd,nevermosby/confd,say5/confd,elbidigital/confd,blippar/confd,shencan/confd,cvrabie/confd,kgrvamsi/confd,fritzy/confd,PrFalken/confd,beni55/confd,gautamk/confd,blippar/confd,axingblog/confd,Fitbit/confd,say5/confd,kgrvamsi/confd,monder/confd,Ropes/confd,aledbf/confd,jnummelin/confd,linearregression/confd,Flipkart/confd,axingblog/confd,alexnauda/confd,philipsoutham/confd,mboersma/confd,israelchen/confd,crandles/confd,tomdee/confd,deis/confd,cloudnautique/confd,okushchenko/confd,okushchenko/confd,jnummelin/confd,agilemobiledev/confd,layerhq/confd,danesparza/confd,mboersma/confd,crunchywelch/confd,glerchundi/confd,glerchundi/renderizr,israelchen/confd,glerchundi/renderizr,rancher/confd,Lineberty/confd