update readme - should now work with alpine linux
update readme - should now work with alpine linux

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