Allow default load and save from/to Google Drive location instead of local memory

[danielinteractive]

Hi Robert,

first of all thanks a lot for the nice app!

I have one main feature request/idea for you. The use case is a family using a single inventory saved on Google Drive (e.g. but probably large demand for that in general I guess).

As far as I can see, currently we have to follow the workflow:

1. import from Google Drive - here we need to select file each time, and also get a warning that existing items have been overwritten
2. do changes in the inventory (or just look up an item)
3. export to Google drive - again we need to select the file each time. This workflow makes it quite cumbersome but it seems the only working way for a multi-user multi-device managed inventory. (If you have other workflows I would definitely be interested!)

In other apps, e.g. https://play.google.com/store/apps/details?id=keepass2android.keepass2android, make this much more comfortable with the following:

1. user can select a default load/save location on Google Drive
2. have an internal cache of that file (e.g. if no internet connection) So this makes it very easy to use multiple devices with a single source of truth on Google Drive.

I think it would enhance the magic home inventory app a lot to have these 2 features - or at least the first one - default load and save from/to a fixed Google Drive location.

What do you think?

Thanks, cheers Daniel