Save a local cache of Dropbox files

[brinux]

To avoid downloading files every time, and also to speed up access, it would be great to have a local cache of the downloaded dropbox files. This may be an option, and/or also include a "maximum space" setting. I'll give a look at the code to see if I can help. Meantime thanks a lot for the great job you're doing!

[mrpdaemon]

This would indeed be a good change. We already implemented a cache layer for the Google Drive file provider to cache file ID mappings, but not content. Doing content caching is probably a smart idea. Would be great if you would like to contribute :)