implement pausing of transfers

A paused transfer's thread keeps running, keeping the slot in use.
This is intentional; pausing a transfer should not let other
queued transfers to run in its place.

Logs/Transfer.hs

@@ -45,6 +45,7 @@ data TransferInfo = TransferInfo
 	, transferRemote :: Maybe Remote
 	, bytesComplete :: Maybe Integer
 	, associatedFile :: Maybe FilePath
+	, transferPaused :: Bool
 	}
 	deriving (Show, Eq, Ord)
 
@@ -93,6 +94,7 @@ runTransfer t file a = do
 		<*> pure Nothing -- not 0; transfer may be resuming
 		<*> pure Nothing
 		<*> pure file
+		<*> pure False
 	bracketIO (prep tfile mode info) (cleanup tfile) a
 	where
 		prep tfile mode info = do
@@ -185,6 +187,7 @@ readTransferInfo pid s =
 			<*> pure Nothing
 			<*> pure Nothing
 			<*> pure (if null filename then Nothing else Just filename)
+			<*> pure False
 		_ -> Nothing
 	where
 		(bits, filebits) = splitAt 1 $ lines s