Delay between adding user vs. availability in the API

[benzittlau]

@nicolas_sabena

GET /api/v2/users/{user-id} and GET /api/v2/users-by-email offer immediate consistency in their results.

BTW, if you had similar end points that supported batch requests (i.e. lists of ids or lists of emails), that would help significantly for my use cases (though still not be as ideal as a performant list endpoint with basic querying).