Ability to define custom audit polcy rules

roles/kubernetes/master/templates/apiserver-audit-policy.yaml.j2

@@ -1,6 +1,9 @@
 apiVersion: audit.k8s.io/v1beta1
 kind: Policy
 rules:
+{% if audit_policy_custom_rules is defined and audit_policy_custom_rules != "" -%}
+{{ audit_policy_custom_rules | indent(2, true) }}
+{% else %}
   # The following requests were manually identified as high-volume and low-risk,
   # so drop them.
   - level: None
@@ -123,3 +126,4 @@ rules:
   - level: Metadata
     omitStages:
       - "RequestReceived"
+{% endif %}