[Feature] Move to remote database

[Taks07]

Please ensure the following for feature requests

• I checked to ensure there aren't other open Pull Requests for the same update/change.

Is your feature request related to a problem? Please describe.

Right now, the database is only locally stored. Depends on #55

Describe the solution you'd like

Create an online database using some free service, and connect to that in the backend instead

Include a user story to describe why you want this feature

As a user, I want to be able access my data on any device so that I don't have to keep using the same one.