jenkins: update to 2.568.1 LTS and chart

Change-Id: Ib6b48599a09dee669d77441c12b354240ef257b8
diff --git a/charts/jenkins/templates/extra-objects.yaml b/charts/jenkins/templates/extra-objects.yaml
new file mode 100644
index 0000000..c8b9a6e
--- /dev/null
+++ b/charts/jenkins/templates/extra-objects.yaml
@@ -0,0 +1,18 @@
+{{- if .Values.extraObjects -}}
+  {{- $extraObjects := .Values.extraObjects -}}
+
+  {{- if kindIs "map" $extraObjects -}}
+    {{- $extraObjects = values $extraObjects -}}
+  {{- end -}}
+
+  {{- range $index, $object := $extraObjects -}}
+    {{- if $object }}
+---
+      {{- if kindIs "string" $object -}}
+        {{- tpl $object $ | nindent 0 -}}
+      {{- else -}}
+        {{- tpl (toYaml $object) $ | nindent 0 -}}
+      {{- end -}}
+    {{- end -}}
+  {{- end -}}
+{{- end -}}