make ugoira webm+preview generation async

app/logical/pixiv_ugoira_converter.rb

@@ -3,6 +3,8 @@ class PixivUgoiraConverter
     folder = Zip::File.new(source_path)
     write_webm(folder, output_path, frame_data)
     write_preview(folder, preview_path)
+    RemoteFileManager.new(output_path).distribute
+    RemoteFileManager.new(preview_path).distribute
   end
 
   def write_webm(folder, write_path, frame_data)

app/logical/pixiv_ugoira_service.rb

@@ -10,7 +10,11 @@ class PixivUgoiraService
   end
 
   def generate_resizes(source_path, output_path, preview_path)
-    PixivUgoiraConverter.new.convert(source_path, output_path, preview_path, @frame_data)
+    PixivUgoiraConverter.delay(:queue => Socket.gethostname).convert(source_path, output_path, preview_path, @frame_data)
+
+    # since the resizes will be delayed, just touch the output file so the
+    # file distribution wont break
+    FileUtils.touch([output_path, preview_path])
   end
 
   def load(data)