Add support for Atikamekw

Language code: atj

Bug: T137376
Change-Id: Ieb9b6bcd09aedbf520b384a6572f96d7db1eca18

RELEASE-NOTES-1.29

@@ -37,6 +37,7 @@ production.
   added to $wgExtraLanguageCodes instead.
 
 === New features in 1.29 ===
+* (T137376) New language support: Atikamekw (atj)
 * (T5233) A cookie can now be set when a user is autoblocked, to track that user
   if they move to a new IP address. This is disabled by default.
 * Added ILocalizedException interface to standardize the use of localized

languages/data/Names.php

@@ -71,6 +71,7 @@ class Names {
 		'as' => 'অসমীয়া', # Assamese
 		'ase' => 'American sign language', # American sign language
 		'ast' => 'asturianu', # Asturian
+		'atj' => 'Atikamekw', # Atikamekw
 		'av' => 'авар', # Avar
 		'avk' => 'Kotava', # Kotava
 		'awa' => 'अवधी', # Awadhi

languages/messages/MessagesAtj.php

@@ -0,0 +1,11 @@
+<?php
+/** Atikamekw
+ *
+ * To improve a translation please visit https://translatewiki.net
+ *
+ * @ingroup Language
+ * @file
+ *
+ */
+
+$fallback = 'fr';