Design how to persist the whole document in local storage

[gustafl]

I imagine the key would look something like this:

fr.document.vingtmillelieuessouslesmers.01

The serial number at the end is for the unlikely case the user loads two documents with the same title.

[gustafl]

Being able to store the last few documents locally might be a good idea, but it's low priority. Also, I don't think an actual Save feature is necessary - only a cache with the last few documents.