message: add xms-ids for peering
diff: "type": "array",
  "items": {
  "$ref": "#/definitions/DirectConnection"
  - }
  + },
  + "x-ms-identifiers": [
  + "connectionIdentifier"
  + ]
  },
  "useForPeeringService": {
  "description": "The flag that indicates whether or not the peering is used for peering service.",
  "type": "array",
  "items": {
  "$ref": "#/definitions/ExchangeConnection"
  - }
  + },
  + "x-ms-identifiers": [
  + "connectionIdentifier"
  + ]
  },
  "peerAsn": {
  "$ref": "#/definitions/SubResource",
  "type": "array",
  "items": {
  "$ref": "#/definitions/Operation"
  - }
  + },
  + "x-ms-identifiers": [
  + "name"
  + ]
  },
  "nextLink": {
  "description": "The link to fetch the next page of peering API operations.",
  "items": {
  "$ref": "#/definitions/MetricSpecification"
  },
  + "x-ms-identifiers": [
  + "name"
  + ],
  "readOnly": true
  }
  }
  "items": {
  "$ref": "#/definitions/MetricDimension"
  },
  + "x-ms-identifiers": [
  + "name"
  + ],
  "readOnly": true
  }
  }
  "type": "array",
  "items": {
  "$ref": "#/definitions/ContactDetail"
  - }
  + },
  + "x-ms-identifiers": [
  + "email"
  + ]
  },
  "peerName": {
  "description": "The name of the peer.",
  "type": "array",
  "items": {
  "$ref": "#/definitions/DirectPeeringFacility"
  - }
  + },
  + "x-ms-identifiers": [
  + "address"
  + ]
  },
  "bandwidthOffers": {
  "description": "The list of bandwidth offers available at the peering location.",
  "type": "array",
  "items": {
  "$ref": "#/definitions/PeeringBandwidthOffer"
  - }
  + },
  + "x-ms-identifiers": [
  + "offerName"
  + ]
  }
  }
  },
  "type": "array",
  "items": {
  "$ref": "#/definitions/ExchangePeeringFacility"
  - }
  + },
  + "x-ms-identifiers": [
  + "exchangeName"
  + ]
  }
  }
  },
  "type": "array",
  "items": {
  "$ref": "#/definitions/PeeringReceivedRoute"
  - }
  + },
  + "x-ms-identifiers": []
  },
  "nextLink": {
  "description": "The link to fetch the next page of received routes for the peering.",
  "items": {
  "$ref": "#/definitions/PeeringServicePrefixEvent"
  },
  + "x-ms-identifiers": [
  + "eventTimestamp"
  + ],
  "readOnly": true
  },
  "peeringServicePrefixKey": {
  