Cannot delete/move the persistent config

[rothcar]

The persistent config is saved automatically by poed. If I delete it, it is automatically reconstituted based on the current poed settings. Since the file is saved as part of background processing by poed, there is no safe way to snapshot the poed state.

[leonchiang]

We'll change code FSM to stop autosave persistent config, and manipulate the config file thought poecli cfg.