ValidateEmail checks that the Email field is not an empty string and that it matches the regex for email addresses, validator.EmailRX.

ValidatePasswordPlaintext validtes that the password is not an empty string and is between 8 and 72 bytes long.

ScopeActivation defines the "activate" scope for scope in the tokens table.

ScopeActivation defines the "activate" scope for scope in the tokens table.

User type whose fields describe a user.

UserModel struct wraps a sql.DB connection pool and allows us to work with the User struct type and the users table in our database.

Permissions holds the permission codes for a single user.