File modified needs to persist until saved

[fgrossman]

A file that is modified and now marked with a dot to indicate it has been modified. That dot and the knowledge that it has changed, has to persist until you know that the file has been saved to a system of record (Google Drive or an XRP).
In the old version of XRPCode we kept that information in local storage. So, even if they refresh the page it shows up as modified.

Also, when I did a CTRL-S with no XRP and no Google login, it gave an error message and then the modified dot disappeared.

[kcq888]

The change is saved in local storage already. We don't currently save the file modification state in local storage.

[kcq888]

Fixed in PR 170