title: Sharing Between Clients in Firebase
body: <p>I would like to know if it is possible to implement Firebase security in such a way as to allow a each user of my app full access to data in their own location, while enabling the user them self's to enable or disable the type of access from other users to their own data? Or basically, is it possible to implement simple sharing, Dropbox or Google Drive style, among the users of my app, in such a way that it is strictly enforced?</p>