Added CS, DA, IT, NL, and PL, minus the .po and .mo starting point files (#16810)

* Added CS, DA, IT, NL, and PL, minus the .po and .mo starting point files

* Add initial PO files for new languages

* Revert updates to EN django.po

---------

Co-authored-by: Jeremy Stretch <jstretch@netboxlabs.com>

README.md

@@ -5,7 +5,7 @@
   <a href="https://github.com/netbox-community/netbox/blob/master/LICENSE.txt"><img src="https://img.shields.io/badge/license-Apache_2.0-blue.svg" alt="License" /></a>
   <a href="https://github.com/netbox-community/netbox/graphs/contributors"><img src="https://img.shields.io/github/contributors/netbox-community/netbox?color=blue" alt="Contributors" /></a>
   <a href="https://github.com/netbox-community/netbox/stargazers"><img src="https://img.shields.io/github/stars/netbox-community/netbox?style=flat" alt="GitHub stars" /></a>
-  <a href="https://explore.transifex.com/netbox-community/netbox/"><img src="https://img.shields.io/badge/languages-10-blue" alt="Languages supported" /></a>
+  <a href="https://explore.transifex.com/netbox-community/netbox/"><img src="https://img.shields.io/badge/languages-15-blue" alt="Languages supported" /></a>
   <a href="https://github.com/netbox-community/netbox/actions/workflows/ci.yml"><img src="https://github.com/netbox-community/netbox/workflows/CI/badge.svg?branch=master" alt="CI status" /></a>
   <p></p>
 </div>

netbox/netbox/settings.py

@@ -739,11 +739,16 @@ RQ_QUEUES.update({
 
 # Supported translation languages
 LANGUAGES = (
+    ('cs', _('Czech')),
+    ('da', _('Danish')),
     ('de', _('German')),
     ('en', _('English')),
     ('es', _('Spanish')),
     ('fr', _('French')),
+    ('it', _('Italian')),
     ('ja', _('Japanese')),
+    ('nl', _('Dutch')),
+    ('pl', _('Polish')),
     ('pt', _('Portuguese')),
     ('ru', _('Russian')),
     ('tr', _('Turkish')),