incremental verification for web special remote

Except when configuration makes curl be used. It did not seem worth
trying to tail the file when curl is downloading.

But when an interrupted download is resumed, it does not read the whole
existing file to hash it. Same reason discussed in
commit 7eb3742e4b; that could take a long
time with no progress being displayed. And also there's an open http
request, which needs to be consumed; taking a long time to hash the file
might cause it to time out.

Also in passing implemented it for git and external special remotes when
downloading from the web. Several others like S3 are within striking
distance now as well.

Sponsored-by: Dartmouth College's DANDI project

Command/AddUrl.hs

@@ -314,7 +314,7 @@ downloadWeb addunlockedmatcher o url urlinfo file =
 	go =<< downloadWith' downloader urlkey webUUID url (AssociatedFile (Just file))
   where
 	urlkey = addSizeUrlKey urlinfo $ Backend.URL.fromUrl url Nothing
-	downloader f p = Url.withUrlOptions $ downloadUrl urlkey p [url] f
+	downloader f p = Url.withUrlOptions $ downloadUrl urlkey p Nothing [url] f
 	go Nothing = return Nothing
 	go (Just tmp) = ifM (pure (not (rawOption o)) <&&> liftIO (isHtmlFile (fromRawFilePath tmp)))
 		( tryyoutubedl tmp

Command/ImportFeed.hs

@@ -173,7 +173,7 @@ downloadFeed url
 	| Url.parseURIRelaxed url == Nothing = giveup "invalid feed url"
 	| otherwise = withTmpFile "feed" $ \f h -> do
 		liftIO $ hClose h
-		ifM (Url.withUrlOptions $ Url.download nullMeterUpdate url f)
+		ifM (Url.withUrlOptions $ Url.download nullMeterUpdate Nothing url f)
 			( Just <$> liftIO (readFileStrict f)
 			, return Nothing
 			)