fix progress reporting during import through the accounts web page

the import was still processed, but the SSE connection to fetch progress did
not work since adding the loggingWriter.

found while working on other functionality that uses SSE.

http/account.go

@@ -129,7 +129,7 @@ func accountHandle(w http.ResponseWriter, r *http.Request) {
 		flusher, ok := w.(http.Flusher)
 		if !ok {
 			log.Error("internal error: ResponseWriter not a http.Flusher")
-			http.Error(w, "500 - internal error - cannot sync to http connection", 500)
+			http.Error(w, "500 - internal error - cannot access underlying connection", 500)
 			return
 		}