fix problem with last commit and assistant

liftAnnex blocks all others calls, so avoid using it with a long-duration
call to readResponse.

Assistant/TransferSlots.hs

@@ -155,7 +155,7 @@ genTransfer t info = case transferRemote info of
 	 - usual cleanup. However, first check if something else is
 	 - running the transfer, to avoid removing active transfers.
 	 -}
-	go remote transferrer = ifM (liftAnnex $ performTransfer transferrer t info)
+	go remote transferrer = ifM (performTransfer transferrer t info)
 		( do
 			case associatedFile info of
 				AssociatedFile Nothing -> noop

Assistant/TransferrerPool.hs

@@ -55,10 +55,17 @@ checkTransferrerPoolItem program batchmaker i = case i of
 
 {- Requests that a Transferrer perform a Transfer, and waits for it to
  - finish. -}
-performTransfer :: Transferrer -> Transfer -> TransferInfo -> Annex Bool
+performTransfer :: Transferrer -> Transfer -> TransferInfo -> Assistant Bool
 performTransfer transferrer t info = catchBoolIO $ do
 	(liftIO $ T.sendRequest t info (transferrerWrite transferrer))
-	T.readResponse (transferrerRead transferrer)
+	readresponse
+  where
+	readresponse = 
+		liftIO (T.readResponse (transferrerRead transferrer)) >>= \case
+			Right r -> return r
+			Left so -> do
+				liftAnnex $ emitSerializedOutput so
+				readresponse
 
 {- Starts a new git-annex transferkeys process, setting up handles
  - that will be used to communicate with it. -}