Fix extension definitions

Before, extensions were missing the definition of mandatory methods.
At the moment, it's not a problem because the coding guidelines are not
enforced by the code. But in the future, it will break.
Now, extensions have all mandatory method definitions.

xExtension-QuickCollapse/extension.php

@@ -1,6 +1,17 @@
 <?php
 
 class QuickCollapseExtension extends Minz_Extension {
+	public function install() {
+		return true;
+	}
+
+	public function uninstall() {
+		return true;
+	}
+
+	public function handleConfigureAction() {
+	}
+
 	public function init() {
 		$this->registerTranslates();
 		$this->registerViews();

xExtension-QuickCollapse/metadata.json

@@ -2,7 +2,7 @@
 	"name": "Quick Collapse",
 	"author": "romibi and Marien Fressinaud",
 	"description": "Quickly change from folded to unfolded articles",
-	"version": 0.1,
+	"version": 0.2,
 	"entrypoint": "QuickCollapse",
 	"type": "user"
 }