update cdn.yml: add azurewebsites(.windows)?.net (#39)

Author: nc7s

src/cdn.yml

@@ -214,6 +214,12 @@ mschcdn.com:
 v0cdn.net:
   name: Microsoft Azure CDN
   link: https://azure.microsoft.com/en-us/services/cdn/
+azurewebsites.net:
+  name: Microsoft Azure App Service
+  link: https://azure.microsoft.com/en-us/services/app-service/
+azurewebsites.windows.net:
+  name: Microsoft Azure App Service
+  link: https://azure.microsoft.com/en-us/services/app-service/
 trafficmanager.net:
   name: Microsoft Azure Traffic Manager
   link: https://azure.microsoft.com/en-us/services/traffic-manager/