[pixiv] create directory for each "work" item (#136)

gallery_dl/extractor/pixiv.py

@@ -29,9 +29,7 @@ class PixivExtractor(Extractor):
 
     def items(self):
         metadata = self.get_metadata()
-
         yield Message.Version, 1
-        yield Message.Directory, metadata
 
         for work in self.works():
             if not work["user"]["id"]:
@@ -46,6 +44,8 @@ class PixivExtractor(Extractor):
             work["tags"] = [tag["name"] for tag in work["tags"]]
             work.update(metadata)
 
+            yield Message.Directory, work
+
             if work["type"] == "ugoira":
                 if not self.load_ugoira:
                     continue