public static void checkForUpdatesAndDownloadAll(final Activity activity, final Download.DownloadType type, @StringRes final int title, final Action1<Boolean> callback) {
        new CheckForDownloadsTask(activity, title, type).execute();
        callback.call(true);
    }
displays an info to the user to check for updates
if button pressed: checks whether updates are available for the type specified
if yes: ask user to download them all
if yes: trigger download(s)
main/src/main/java/cgeo/geocaching/downloader/DownloaderUtils.java