remount boot media with RW flag

[Axel <axel.ml@laposte.net>]

Hello

I m using a Debian Live system on flash devices (compactflash and USB 
drives). I m using persistence with hard disks partitions.
I d like to save some files on the flash device, which is mounted as 
read-only.
My idea is to remount the device as read-write in a hook at boot time, 
by including a file like chroot_local-includes/lib/live/config/200-remount

Is there something better than this ?

Thanks for your answer