GUI: add CLI equivalent dialog (#163); use spinboxes in Sequence dialog

and restrict sequence to max 10,000, add button icons;
   make Export dialog sizable and show every 100 results, add button icon;
   fix saving CHANNEL option, fix Export painting main window (Windows), fix
   guard descent not-resetting
 qzint: add getAsCLI(), warnLevel(), extra isStackable()/isComposite() etc
 Add ZBarcode_BarcodeName()
 manual: doc above, some fixes, tweaks

frontend_qt/cliwindow.h

@@ -0,0 +1,46 @@
+/*
+    Zint Barcode Generator - the open source barcode generator
+    Copyright (C) 2021 Robin Stuart <rstuart114@gmail.com>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+/* vim: set ts=4 sw=4 et : */
+
+#ifndef CLIWINDOW_H
+#define CLIWINDOW_H
+
+#include "ui_extCLI.h"
+
+class BarcodeItem;
+
+class CLIWindow : public QDialog, private Ui::CLIDialog
+{
+    Q_OBJECT
+
+public:
+    CLIWindow(BarcodeItem *bc, const bool autoHeight, const double heightPerRow);
+    virtual ~CLIWindow();
+
+private slots:
+    void copy_to_clipboard();
+    void generate_cli();
+
+protected:
+    BarcodeItem *m_bc;
+    bool m_autoHeight;
+    double m_heightPerRow;
+};
+
+#endif