Sync message about quota limit

[drweb86]

    var skippedBecauseOfQuotaFiles = WriteFileTasks
        .Where(x => x.IsSkippedBecauseOfQuota)
        .SelectMany(x => x.StorageFiles)
        .ToList();
    if (skippedBecauseOfQuotaFiles.Any())
    {
        var gigabyte = 1024 * 1024 * 1024;
        Events.Message(string.Format(BUtil.Core.Localization.Resources.Task_Status_PartialDueToQuota, skippedBecauseOfQuotaFiles.Count, skippedBecauseOfQuotaFiles.Sum(x => x.FileState.Size) / gigabyte));
    }