Turn unnecessary class into namespace

(cherry picked from commit 34165c7b2b)

game/scripts/doll/main.rpy

@@ -538,7 +538,7 @@ init python:
             # Grab data
             if fromfile:
                 try:
-                    imported = ImagePayload().extract(path)
+                    imported = image_payload.extract(path)
                 except Exception as e:
                     renpy.notify("Import failed: Corrupted file.")
                     print(e)

game/scripts/doll/outfits.rpy

@@ -222,7 +222,7 @@ init python:
                 )
 
                 displayable_to_file(d, path, size=(310, 470) )
-                ImagePayload().inject("_temp.png", filename, str(exported))
+                image_payload.inject("_temp.png", filename, str(exported))
                 os.remove(path)
             else:
                 set_clipboard(exported)