replace media_post with media_path, now media_posts are dropped

LogBot/logbot.py

@@ -202,7 +202,7 @@ class Logbot(Bot):
         if message.url:
             media_type, media_mime, media_path, media_size = self._download(message)
             # TODO: Insert a list of accepted file types here.
-            if media_post:
+            if media_path:
                 num = self._add_to_db(message, media_type=media_mime, media_path=media_path, media_size=media_size)
                 media_type = media_type.replace("images", "image") # linguistic hack!
                 if 'pdf' in message.url: