Update README.md (#1375)
Update README.md (#1375)

More minor textual fixes.
miekg/coredns,ii/coredns,jremond/coredns,johnbelamaric/coredns,johnbelamaric/coredns,miekg/coredns,ii/coredns,yongtang/coredns,jremond/coredns,chrisohaver/coredns,coredns/coredns