fix(etcd guide): fix relative linking errors causing 404s
fix(etcd guide): fix relative linking errors causing 404s

coreos/docs,wli6/docs,marineam/coreos-docs,endocode/coreos-docs,joshix/docs,mischief/coreos-docs,hkjn/docs-1,jonboulle/docs,mjg59/docs,atxwebs/docs,skynet/docs,jdloft/docs,ionave/docs,ksmaheshkumar/docs-2,michelleN/docs,iankronquist/docs,bq-xiao/docs,robszumski/docs