macosx: Confirm that the crash report has been sent.

modules/gui/macosx/intf.m

@@ -2125,6 +2125,9 @@ end:
 
 - (void)connectionDidFinishLoading:(NSURLConnection *)connection
 {
+    NSRunInformationalAlertPanel(_NS("Crash Log successfully sent"),
+                _NS("Thanks for your report!"),
+                _NS("OK"), nil, nil, nil);
     [connection release];
 }