Restore Magic Latern files after a format

[Jason Gerard DeRose]

Magic Latern is a popular firmware project that can make Canon HDSLR much more practical for video production:

http://magiclantern.wikia.com/wiki/Magic_Lantern_Firmware_Wiki

It's important for Dmedia (at the user's option) to automatically format cards after an import completes, but when the Magic Lantern files are found on a card, we should restore them after the format, as discussed here:

http://vimeo.com/groups/novacutartistdiaries/videos/32867613

We also want to preserve (and extract) the useful extra metadata that magic lantern creates.

For background, please see this section of the file import UX design on why automatically formatting the cards helps reduce the chance of data loss:

https://wiki.ubuntu.com/AyatanaDmediaLovefest#Automatically_format_the_cards_when_safe

[Jason Gerard DeRose (jderose)]

Quick status update on this: So the blocking issue here is that Dmedia doesn't have permission to re-mount the media after the format. I'm not sure if UDisks and/or PolicyKit have a re-mount action that's distinct from mounting. We don't need permission to mount, just re-mount.

Also, looks like we need to switch to UDisks2 for Quantal. I want to work with the needed upstreams to make the Dmedia import scenario something official supported, something we can count on release after release:

https://wiki.ubuntu.com/Novacut/HelpNeeded#UDisks2