Application Gateway - Adds Rewrite rule set for Header CRUD (#4331)

* Adds base for updating Microsoft.Network from version stable/2018-08-01 to version 2018-10-01

* Updates readme

* Updates API version in new specs and examples

* Adds Rewrite rule set for Header CRUD

Adds the structure of rewriteRuleSets in the applicationGatewayProperties.
Adds recursively the sub structures in the rewriteRuleSet.
Adds the reference to rewriteRuleSet in the requestRoutingRule for both Basic rule and Path based rule.

* Adds examples for the Header CRUD in application gateway

* Fix the examples; replacing rules with rewriteRules.

* Fixing the properties of application Gateway rewriteRule

* Revert "Fixing the properties of application Gateway rewriteRule"

This reverts commit 05c9c91.

* Fixing the properties of application Gateway rewriteRule

* Mark the provisioning state as readOnly

* Mark etag as readOnly

specification/network/resource-manager/Microsoft.Network/stable/2018-10-01/applicationGateway.json

@@ -1275,6 +1275,10 @@
           "$ref": "./network.json#/definitions/SubResource",
           "description": "Redirect configuration resource of URL path map path rule."
         },
+        "rewriteRuleSet": {
+          "$ref": "./network.json#/definitions/SubResource",
+          "description": "Rewrite rule set resource of URL path map path rule."
+        },
         "provisioningState": {
           "type": "string",
           "description": "Path rule of URL path map resource. Possible values are: 'Updating', 'Deleting', and 'Failed'."
@@ -1437,6 +1441,10 @@
           "$ref": "./network.json#/definitions/SubResource",
           "description": "URL path map resource of the application gateway."
         },
+        "rewriteRuleSet": {
+          "$ref": "./network.json#/definitions/SubResource",
+          "description": "Rewrite Rule Set resource in Basic rule of the application gateway."
+        },
         "redirectConfiguration": {
           "$ref": "./network.json#/definitions/SubResource",
           "description": "Redirect configuration resource of the application gateway."
@@ -1474,6 +1482,88 @@
       ],
       "description": "Request routing rule of an application gateway."
     },
+    "ApplicationGatewayRewriteRuleSet": {
+      "properties": {
+        "properties": {
+          "x-ms-client-flatten": true,
+          "$ref": "#/definitions/ApplicationGatewayRewriteRuleSetPropertiesFormat"
+        },
+        "name": {
+          "type": "string",
+          "description": "Name of the rewrite rule set that is unique within an Application Gateway."
+        },
+        "etag": {
+          "readOnly": true,
+          "type": "string",
+          "description": "A unique read-only string that changes whenever the resource is updated."
+        }
+      },
+      "allOf": [
+        {
+          "$ref": "./network.json#/definitions/SubResource"
+        }
+      ],
+      "description": "Rewrite rule set of an application gateway."
+    },
+    "ApplicationGatewayRewriteRuleSetPropertiesFormat": {
+      "properties": {
+        "rewriteRules": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/ApplicationGatewayRewriteRule"
+          },
+          "description": "Rewrite rules in the rewrite rule set."
+        },
+        "provisioningState": {
+          "readOnly": true,
+          "type": "string",
+          "description": "Provisioning state of the rewrite rule set resource. Possible values are: 'Updating', 'Deleting', and 'Failed'."
+        }
+      },
+      "description": "Properties of rewrite rule set of the application gateway."
+    },
+    "ApplicationGatewayRewriteRule": {
+      "properties": {
+        "name": {
+          "type": "string",
+          "description": "Name of the rewrite rule that is unique within an Application Gateway."
+        },
+        "actionSet": {
+          "type": "object",
+          "$ref": "#/definitions/ApplicationGatewayRewriteRuleActionSet",
+          "description": "Set of actions to be done as part of the rewrite Rule."
+        }
+      },
+      "description": "Rewrite rule of an application gateway."
+    },
+    "ApplicationGatewayRewriteRuleActionSet": {
+      "properties": {
+        "requestHeaderConfigurations": {
+          "type": "array",
+          "$ref": "#/definitions/ApplicationGatewayHeaderConfiguration",
+          "description": "Request Header Actions in the Action Set"
+        },
+        "responseHeaderConfigurations": {
+          "type": "array",
+          "$ref": "#/definitions/ApplicationGatewayHeaderConfiguration",
+          "description": "Response Header Actions in the Action Set"
+        }
+      },
+      "description": "Set of actions in the Rewrite Rule in Application Gateway."
+    },
+    "ApplicationGatewayHeaderConfiguration": {
+      "properties": {
+        "headerName": {
+          "type": "string",
+          "description": "Header name of the header configuration"
+        },
+        "headerValue": {
+          "type": "string",
+          "description": "Header value of the header configuration"
+        }
+      },
+      "description": "Header configuration of the Actions set in Application Gateway."
+    },
     "ApplicationGatewayRedirectConfigurationPropertiesFormat": {
       "properties": {
         "redirectType": {
@@ -1660,6 +1750,13 @@
           },
           "description": "Request routing rules of the application gateway resource."
         },
+        "rewriteRuleSets": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/ApplicationGatewayRewriteRuleSet"
+          },
+          "description": "Rewrite rules for the application gateway resource."
+        },
         "redirectConfigurations": {
           "type": "array",
           "items": {
@@ -1752,6 +1849,10 @@
           "$ref": "./network.json#/definitions/SubResource",
           "description": "Default backend http settings resource of URL path map."
         },
+        "defaultRewriteRuleSet": {
+          "$ref": "./network.json#/definitions/SubResource",
+          "description": "Default Rewrite rule set resource of URL path map."
+        },
         "defaultRedirectConfiguration": {
           "$ref": "./network.json#/definitions/SubResource",
           "description": "Default redirect configuration resource of URL path map."