Update Docs and Manifests for v0.20.0

* Added v0.20 references to README
* Update k8s manifests with v0.20.0 references

README.md

@@ -521,6 +521,7 @@ packages that it is compiled with.
 
 Descheduler  | Supported Kubernetes Version
 -------------|-----------------------------
+v0.20        | v1.20
 v0.19        | v1.19
 v0.18        | v1.18
 v0.10        | v1.17

kubernetes/cronjob/cronjob.yaml

@@ -16,7 +16,7 @@ spec:
           priorityClassName: system-cluster-critical
           containers:
           - name: descheduler
-            image: k8s.gcr.io/descheduler/descheduler:v0.19.0
+            image: k8s.gcr.io/descheduler/descheduler:v0.20.0
             volumeMounts:
             - mountPath: /policy-dir
               name: policy-volume

kubernetes/job/job.yaml

@@ -14,7 +14,7 @@ spec:
       priorityClassName: system-cluster-critical
       containers:
         - name: descheduler
-          image: k8s.gcr.io/descheduler/descheduler:v0.19.0
+          image: k8s.gcr.io/descheduler/descheduler:v0.20.0
           volumeMounts:
           - mountPath: /policy-dir
             name: policy-volume