Upload photos to tag slug subdirectory.

controllers/UploadMedia.php

@@ -36,6 +36,7 @@ class UploadMedia extends HTMLController
 				$asset = Asset::createNew([
 					'filename_to_copy' => $uploaded_file['tmp_name'],
 					'preferred_filename' => $uploaded_file['name'],
+					'preferred_subdir' => $tag->slug,
 				]);
 
 				$new_ids[] = $asset->getId();