Performs a Get against the global UsersStore, and if the User
already exists, it appends to that User instead of trying to add
the "new" User blindly.
Signed-off-by: Michael de Sa <mjdesa@gmail.com>
bolt/organization_users_store contains a boltdb implementation of a
chronograf.UsersStore that filters the results based on the organization
that is set on the context.
Signed-off-by: Jared Scheib <jared.scheib@gmail.com>