Rework auth for private groups

[BenReichwein]

Using the auth branch. Add to the user schema to have authenticatedGroups so whenever a user is logged to any device they will be able to join group without password.

Also if you're up for even more of a challenge we need to add another field (adminGroups) so when a user creates a group it adds to that users schema.

If you've got any questions please reach out.