Clarify the license as defined in debian/copyright and switch to spdx format (#81)

Author: leigh123linux

README.md

@@ -18,4 +18,4 @@ The PO files in this project are imported from there.
 
 # License
 
-- Code: GPLv3
+- Code: GPL-3.0-or-later

debian/copyright

@@ -5,7 +5,7 @@ Source: https://github.com/linuxmint/bulky
 
 Files: *
 Copyright: 2021 Linux Mint <[email protected]>
-License: GPL-3+
+License: GPL-3.0-or-later
  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
@@ -17,4 +17,4 @@ License: GPL-3+
  GNU General Public License for more details.
  .
  On Debian systems, the complete text of the GNU General
- Public License can be found in `/usr/share/common-licenses/GPL'
+ Public License can be found in `/usr/share/common-licenses/GPL-3'

usr/lib/bulky/bulky.py

@@ -438,7 +438,7 @@ def open_about(self, widget):
         dlg.set_program_name("Bulky")
         dlg.set_comments(_("Rename Files"))
         try:
-            with open('/usr/share/common-licenses/GPL', encoding="utf-8") as h:
+            with open('/usr/share/common-licenses/GPL-3', encoding="utf-8") as h:
                 gpl= h.read()
             dlg.set_license(gpl)
         except Exception as e: