Fallback to default config when nothing set
Fallback to default config when nothing set

tuannvm/skydns,vinhhrv/skydns,erimatnor/skydns-kubernetes,nicescale/skydns,skynetservices/skydns,ZeaLoVe/skydns,netf/skydns,no2key/skydns,andrewrothstein/skydns,zvelo/zvelo-skydns,weekface/skydns,tonicbupt/skydns,smarterclayton/skydns,zhang0137/skydns,hw-qiaolei/skydns,AdoHe/skydns,yonglehou/skydns,loveshell/skydns