remove unused usings
remove unused usings

projectkudu/TryAppService,projectkudu/SimpleWAWS,projectkudu/TryAppService,fashaikh/SimpleWAWS,projectkudu/TryAppService,davidebbo/SimpleWAWS,projectkudu/SimpleWAWS,projectkudu/SimpleWAWS,fashaikh/SimpleWAWS,fashaikh/SimpleWAWS,davidebbo/SimpleWAWS,projectkudu/TryAppService,davidebbo/SimpleWAWS,projectkudu/SimpleWAWS,fashaikh/SimpleWAWS,davidebbo/SimpleWAWS