A user is a login and password combination that identifies individuals entitled to use Lumeta. Lumeta=> Username can be a combination of alphanumeric characters but cannot start with number.
- Use this set of characters: A-Za-z0-9_.-
- Are one or more characters (but not a single dot, digit or hyphen)
- Do not start with a hyphen
- If the id starts with a dot, then there has to be at least one non-dot character afterwards
- If the id starts with a number, then there must be one non-numeric character afterwards