Req: move/copy queue functionality for mc

[Sergioo]

I copied recently more files between disks in 320L and lacked functionality of queuing copy/move tasks (like in Total Commander). Midnight Commander run all copy/move tasks putting in background in parallel, this gives worst throuput than one operation in time only. These tasks can be stopped/started manually, but this needs waiting for end of every single move/copy operation. But ... I found small patch for mc, that add queuing background tasks instead instant run next copy/move (patch auto stop every new task and run sequentially one at time.

Source: https://midnight-commander.org/ticket/2240