Allow setting URL slug through admin panel.

models/Asset.php

@@ -314,6 +314,11 @@ class Asset
 		return ASSETSDIR . '/' . $this->subdir . '/' . $this->filename;
 	}
 
+	public function getSlug()
+	{
+		return $this->slug;
+	}
+
 	public function getSubdir()
 	{
 		return $this->subdir;
@@ -535,11 +540,12 @@ class Asset
 			FROM assets');
 	}
 
-	public function setKeyData($title, DateTime $date_captured = null, $priority)
+	public function setKeyData($title, $slug, DateTime $date_captured = null, $priority)
 	{
 		$params = [
 			'id_asset' => $this->id_asset,
 			'title' => $title,
+			'slug' => $slug,
 			'priority' => $priority,
 		];
 
@@ -548,7 +554,8 @@ class Asset
 
 		return Registry::get('db')->query('
 			UPDATE assets
-			SET title = {string:title},' . (isset($date_captured) ? '
+			SET title = {string:title},
+				slug = {string:slug},' . (isset($date_captured) ? '
 				date_captured = {datetime:date_captured},' : '') . '
 				priority = {int:priority}
 			WHERE id_asset = {int:id_asset}',