Modify glance element to preserve state

We use the file backend currently so we need to preserve the uploaded
images in /mnt/state.

Change-Id: I8351c8becffe901c9223569458b6448c60ff0236
Don't chown /var/lib/misc/

This doesn't seem to be needed and I can't see what needed it in the
past. Looks like it got added in the original nova element.

Change-Id: Idf84fbff87675d0a25ceb1f7d09a1528db9c2b58
Merge "Modify glance element to preserve state"
Merge "Don't chown /var/lib/misc/"