Local storage for documents

[awmartin]

Motivation

When my computer isn't connected to the Internet, I need a way to edit offline. Or I don't want to use a hosted service like Firebase, so I want to edit all of my docs locally.

Design

Need a way to pick the specify the deployment backend in code.

Or a setting to sync to a local destination while using a remote hosting service.

[awmartin]

This may be best implemented as a sync destination for an Electron wrapper, so both Firebase and the local system can be targeted. A local file system backend has already been implemented with Express.