Super-admin role account

[myeti]

Is your feature request related to a problem? Please describe.
The UI is missing account management with super-admin, admin and user roles.
When publicly exposed, anyone can create an account and use CompreFace without any validation nor management.

Describe the solution you'd like

1. Account creation

• Public account creation is only available for the first user, which will be promoted super-admin
• Once a super-admin is created and active, public account creation is disabled
• Only super-admins can manage accounts (creation, deletion)
• Upon creation, a private link will be generated for the newly created user to input his password

2. User management

• Super-admin can create apps and assign admin
• Admin can create services and assign standard user

Strapi is a good exemple of this process.

Thank you :)