Users are allowed to register without entering an e-mail address even if registration must be validated by e-mail

Steps to reproduce:

• Login as an admin
• Go to Administration -> Email and fill in the required fields
• Go to Administration -> Registration and set both "Use email Verification" and "Authentication Active Check" to "Yes"
• Log-out
• Click on "Register" and fill in the required fields (username and password twice); "Email Address" should also be required (registration.png)
• Click "Register"; you see a message telling you that the registration is successful (success.png)
• Click "Log-in"; you see a notice asking you for a validation key (validation.png), but you can't activate and use your account if you didn't fill in the email address in the "Registration" step