add 1.8.1 draft notes (#4263)

* add 1.8.1 draft notes

Start the list of note worth PRs
Signed-off-by: Miek Gieben <miek@miek.nl>

* forgot k8s
Signed-off-by: Miek Gieben <miek@miek.nl>

notes/coredns-1.8.1.md

++++
+title = "CoreDNS-1.8.1 Release"
+description = "CoreDNS-1.8.1 Release Notes."
+tags = ["Release", "1.8.1", "Notes"]
+release = "1.8.1"
+date = 2020-12-22T08:00:00+00:00
+author = "coredns"
+draft = true
++++
+
+DRAFT DRAFT DRAFT
+
+The CoreDNS team has released
+[CoreDNS-1.8.1](https://github.com/coredns/coredns/releases/tag/v1.8.1).
+
+## Brought to You By
+
+## Noteworthy Changes
+
+* plugin/{clouddns,azure,route53}: Use cancelable contexts for cloud provider plugin refreshes (https://github.com/coredns/coredns/pull/4226)
+* plugin/health: Fix health check endpoint (https://github.com/coredns/coredns/pull/4231)
+* plugin/local: add local plugin (https://github.com/coredns/coredns/pull/4262)
+* plugin/kubernetes: plugin/kubernetes: Watch EndpointSlices (https://github.com/coredns/coredns/pull/4209)