switch to extension registration, proper i18n

HeaderFooter.php

@@ -1,22 +1,14 @@
 <?php
-/**
- * @author Jean-Lou Dupont
- * @author Jamesmontalvo3
- * @package HeaderFooter
- * @version 2.1.1
- */
-
-# Credits
-$GLOBALS['wgExtensionCredits']['other'][] = array( 
-	'name'		  => 'HeaderFooter', 
-	'version'	  => '2.1.1',
-	'author'	  => 'Jean-Lou Dupont, James Montalvo, Douglas Mason', 
-	'description' => 'Enables per-page/per-namespace headers and footers',
-	'url' 		  => 'http://mediawiki.org/wiki/Extension:HeaderFooter',			
-);
-
-# Hooks
-$GLOBALS['wgHooks']['OutputPageParserOutput'][] = 'HeaderFooter::hOutputPageParserOutput';
-
-# Autoload
-$GLOBALS['wgAutoloadClasses']['HeaderFooter'] = __DIR__ . '/HeaderFooter.class.php';
+if ( function_exists( 'wfLoadExtension' ) ) {
+	wfLoadExtension( 'HeaderFooter' );
+	// Keep i18n globals so mergeMessageFileList.php doesn't break
+	$wgMessagesDirs['HeaderFooter'] = __DIR__ . '/i18n';
+	wfWarn(
+		'Deprecated PHP entry point used for HeaderFooter extension. ' .
+		'Please use wfLoadExtension instead, ' .
+		'see https://www.mediawiki.org/wiki/Extension_registration for more details.'
+	);
+	return;
+} else {
+	die( 'This version of the HeaderFooter extension requires MediaWiki 1.25+' );
+}

extension.json

@@ -0,0 +1,17 @@
+{
+	"name": "HeaderFooter",
+	"version": "3.0.0",
+	"author": "Jean-Lou Dupont, James Montalvo, Douglas Mason",
+	"url": "http://mediawiki.org/wiki/Extension:HeaderFooter",
+	"descriptionmsg": "headerfooter-desc",
+	"type": "other",
+	"AutoloadClasses": {
+		"HeaderFooter": "HeaderFooter.class.php"
+	},
+	"Hooks": {
+		"OutputPageParserOutput": [
+			"HeaderFooter::hOutputPageParserOutput"
+		]
+	},
+	"manifest_version": 1
+}

i18n/en.json

@@ -0,0 +1,3 @@
+{
+	"headerfooter-desc": "Enables per-page/per-namespace headers and footers"
+}