datasource as cfg: add org_id to example config

conf/datasources.yaml

@@ -12,7 +12,9 @@ datasources:
 #   type: graphite
 #   # <string, required> access mode. direct or proxy. Required
 #   access: proxy
-#     # <string, required> url
+#   # <int> org id. will default to org_id 1 if not specified
+#   org_id: 1
+#   # <string> url
 #   url: http://localhost:8080
 #   # <string> database password, if used
 #   password:
@@ -34,6 +36,9 @@ datasources:
 #   json_data: '{"graphiteVersion":"0.9"}'
 #   # <string> json object of data that will be encrypted in UI.
 #   secure_json_fields: ''
+#   # <int> including this value garantees that instance with old configs cannot
+#   #       overwrite your last change.
+#   version: 1
 # - name: Prometheus
 #   type: prometheus
 #   access: proxy