added primary flag to the NetworkInterfaceIPConfigurationPropertiesFormat object of networkInterface.json definition of Network 2015-06-15 spec (#3200)

Author: seyadava

specification/network/resource-manager/Microsoft.Network/stable/2015-06-15/networkInterface.json

@@ -275,6 +275,10 @@
         "subnet": {
           "$ref": "./virtualNetwork.json#/definitions/Subnet"
         },
+        "primary": {
+          "type": "boolean",
+          "description": "Gets whether this is a primary customer address on the network interface."
+        },
         "publicIPAddress": {
           "$ref": "./publicIpAddress.json#/definitions/PublicIPAddress"
         },