Allow deleting attachments with their files already deleted

boards/signals.py

@@ -126,10 +126,16 b' def rebuild_refmap(instance, **kwargs):'
 def delete_file(instance, **kwargs):
     if instance.is_internal():
         file = MEDIA_ROOT + instance.file.name
-        os.remove(file)
+        try:
+            os.remove(file)
+        except FileNotFoundError:
+            pass
         if instance.mimetype in FILE_TYPES_IMAGE:
             for size in THUMB_SIZES:
                 file_name_parts = instance.file.name.split('.')
                 thumb_file = MEDIA_ROOT + '{}.{}x{}.{}'.format(file_name_parts[0], size[0], size[1], file_name_parts[1])
-                os.remove(thumb_file)
+                try:
+                    os.remove(thumb_file)
+                except FileNotFoundError:
+                    pass
 

boards/views/tag_gallery.py

@@ -18,7 +18,8 b' class TagGalleryView(BaseBoardView, Pagi'
         page = int(request.GET.get('page', 1))
 
         params = dict()
-        tag = get_object_or_404(Tag, name=tag_name)
+        tag_alias = get_object_or_404(TagAlias, name=tag_name)
+        tag = tag_alias.parent
         params['tag'] = tag
         paginator = get_paginator(tag.get_images(), IMAGES_PER_PAGE,
                                   current_page=page)