pkg/up: stop *all* goroutines (#1676)
pkg/up: stop *all* goroutines (#1676)

Stop all goroutines after we get the stop signal.
miekg/coredns,johnbelamaric/coredns,jremond/coredns,johnbelamaric/coredns,coredns/coredns,chrisohaver/coredns,miekg/coredns,ii/coredns,yongtang/coredns,ii/coredns,jremond/coredns