private void Mi_ChangeFile_Click(object sender, RoutedEventArgs e)
        {
            ChangeFile cf = new ChangeFile(FileHandling.allTags, selectedWF);

            if (cf.ShowDialog() == true)
            {
                changeItem(cf.sourceFile);
                //addItem(cf.sourceFile);
            }
        }
        private void Mi_AddFile_Click(object sender, RoutedEventArgs e)
        {
            ChangeFile cf = new ChangeFile(FileHandling.allTags, new ViewModels.WatchedFile());

            if (cf.ShowDialog() == true)
            {
                addItem(cf.sourceFile);
                foreach (Tag t in cf.sourceFile.Tags)
                {
                    if (!FileHandling.allTags.Contains(t))
                    {
                        FileHandling.allTags.Add(t);
                    }
                }
            }
        }