add sleep in web request

src/gui/thumbnail_thread.cpp

@@ -57,7 +57,7 @@ ThumbnailThreadWorker::ThumbnailThreadWorker(ThumbnailThread* parent)
 wxThread::ExitCode ThumbnailThreadWorker::Entry() {
   while (true) {
     do {
-      Sleep(1);
+      wxMilliSleep(1);
     } while (stop);
     // get a request
     {

src/gui/web_request_window.cpp

@@ -59,6 +59,7 @@ WebRequestWindow::WebRequestWindow(Window* parent, const String& url, bool sizer
   });
 
   // start request
+  wxMilliSleep(70); // make sure we don't DDoS anyone
   request.Start();
 }