Doc update re effective directive and default conf
Doc update re effective directive and default conf

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codelion/secureheaders,twitter/secureheaders,reedloden/secureheaders,reedloden/secureheaders,codelion/secureheaders,jacobbednarz/secureheaders,didacte/secureheaders,eoy/secureheaders,wlchou/secureheaders,wlchou/secureheaders,didacte/secureheaders,reedloden/secureheaders,didacte/secureheaders,davidhan527/secureheaders,eoy/secureheaders,codelion/secureheaders,eoy/secureheaders,wlchou/secureheaders