webapp: Only show up to 10 queued transfers.

The transfer queue can grow larger than 10 when queueing transfers for
files that were just received, as well as requeueing failed transfers.
I probably need to do some work to prevent that, as it could use a lot of
RAM. But for now, cap the number of displayed transfers in the webapp, to
avoid flooding the browser.

Assistant/WebApp/DashBoard.hs

@@ -33,7 +33,7 @@ transfersDisplay :: Bool -> Widget
 transfersDisplay warnNoScript = do
 	webapp <- lift getYesod
 	current <- lift $ M.toList <$> getCurrentTransfers
-	queued <- lift $ liftAssistant getTransferQueue
+	queued <- lift $ take 10 <$> liftAssistant getTransferQueue
 	autoUpdate ident NotifierTransfersR (10 :: Int) (10 :: Int)
 	let transfers = simplifyTransfers $ current ++ queued
 	if null transfers