Persist

RSP sessions can now be made persistent (can survive to a server complete restart). Currently sessions and mail queues can be persisted.

The sessions are saved on a graceful shutdown to a hidden file named .rsp-sessions in cheyenne's startup directory (join system/options/path %.rsp-sessions). On startup this file is loaded and immediately gets deleted, so during runtime sessions content are not observable through this file.

Example usage:

    persist [sessions mail-queue]

Other flags can be added at will too.