Refactor email_format_validator_test.rb and password_format_validator_test.rb
Refactor email_format_validator.rb and password_format_validator.rb

Refactor email_format_validator_test.rb and password_format_validator_test.rb
Refactor email_format_validator.rb and password_format_validator.rb
Map db exceptions to model errors

Add TODO to map db exceptions to model errors
Add TODO to map db exceptions to model errors
