wrap ResponseWriter to log/stat non-200 status code from http.FileServer
wrap ResponseWriter to log/stat non-200 status code from http.FileServer

keybase/client,keybase/kbfs,keybase/kbfs,keybase/kbfs,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/kbfs,keybase/client,keybase/client,keybase/client,keybase/client