look up --to and --from remote names only once

This will speed up commands like move and drop.

Command/Move.hs

@@ -29,20 +29,17 @@ options :: [Option]
 options = [fromOption, toOption]
 
 seek :: [CommandSeek]
-seek = [withField "to" id $ \to -> withField "from" id $ \from ->
-		withFilesInGit $ whenAnnexed $ start to from True]
+seek = [withField "to" Remote.byName $ \to ->
+		withField "from" Remote.byName $ \from ->
+			withFilesInGit $ whenAnnexed $ start to from True]
 
-start :: Maybe String -> Maybe String -> Bool -> FilePath -> (Key, Backend) -> CommandStart
+start :: Maybe Remote -> Maybe Remote -> Bool -> FilePath -> (Key, Backend) -> CommandStart
 start to from move file (key, _) = do
 	noAuto
 	case (from, to) of
 		(Nothing, Nothing) -> error "specify either --from or --to"
-		(Nothing, Just name) -> do
-			dest <- Remote.byName name
-			toStart dest move file key
-		(Just name, Nothing) -> do
-			src <- Remote.byName name
-			fromStart src move file key
+		(Nothing, Just dest) -> toStart dest move file key
+		(Just src, Nothing) -> fromStart src move file key
 		(_ ,  _) -> error "only one of --from or --to can be specified"
 	where
 		noAuto = when move $ whenM (Annex.getState Annex.auto) $ error