6.1.1 migrate database
6.1.2 annotate model
6.2.1 prepare initial user tests
6.2.2 green model validations
6.2.3 green validation for length
6.2.4 green validation for email format
6.2.5 green validation for almost uniqueness
6.2.5 green validation for uniqueness; generate index for email
6.3.1 green encrypted password
6.3.2 red password confirmation
6.3.3 red authentication
6.3.4 green secure password