Move xos-db into it's own chart

Have it issue it's own PersistentVolumeClaim if required

Change-Id: I408559b2cf4481e011e47c310147fd36c8c284bc
diff --git a/xos-db/templates/_persist.tpl b/xos-db/templates/_persist.tpl
new file mode 100644
index 0000000..ee6fb9b
--- /dev/null
+++ b/xos-db/templates/_persist.tpl
@@ -0,0 +1,30 @@
+{{- /*
+Copyright 2017-present Open Networking Foundation
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/ -}}
+{{- define "xos-db.persistent-volume-claim" }}
+---
+kind: PersistentVolumeClaim
+apiVersion: v1
+metadata:
+  name: {{ .Values.pvClaimName }}
+spec:
+  accessModes:
+    - ReadWriteOnce
+  storageClassName: {{ .Values.storageClassName }}
+  resources:
+    requests:
+      storage: 1Gi
+{{- end }}
+