save working session (area list, tile list, %cloud, date) and have option to load it later

[wscullen]

Should add a menu option to save out the localstorage.json file and to load. Can use the same file select dialog used to save the tile list json file out.

This will be moot once we move to a database driven solution with redux (imaging using firebase or mongo or something similar), but that move won't be for a long time.