/// <summary>
        /// Handles the Click event of the btn_ProjImport control.
        /// </summary>
        /// <param name="sender">The source of the event.</param>
        /// <param name="e">The <see cref="EventArgs"/> instance containing the event data.</param>
        /// Erstellt von Veit Berg, am 27.01.16
        private void btn_ProjImport_Click(object sender, EventArgs e)
        {
            string         exportFilePath = "";
            OpenFileDialog ofd            = new OpenFileDialog();

            ofd.Filter = "Zip Files|*.zip";
            ofd.Title  = "Wähle Exportdatei";
            if (ofd.ShowDialog() == DialogResult.OK)
            {
                exportFilePath = ofd.FileName;
            }
            if (exportFilePath != "")
            {
                try
                {
                    ProjectImporter projImporter = new ProjectImporter(exportFilePath);
                    projImporter.ImportWholeProject();
                }
                catch (Exception exception)
                {
                    MessageBox.Show(exception.Message);
                }
            }
            RefreshDropDown();
        }