Add 'EmailConfirmed' checking before sending notification emails when 'RequireConfirmedEmail' is true

[erwindevreugd]

Right now we only check the value of CanNotify on CoreWikiUser if we can send emails to a user.

We should also check the value of EmailConfirmed in the AspNetUsers table to detirmine if we can send emails to a user. This should take into account the value of the RequireConfirmedEmail application setting.

Notification Emails

EmailConfirmed	RequireConfirmedEmail	CanNotify	Action
False	False	False	Don't send
False	False	True	Send
False	True	False	Don't send
False	True	True	Don't send
True	False	False	Don't send
True	False	True	Send
True	True	False	Don't send
True	True	True	Send

Forgot Password Email

EmailConfirmed	RequireConfirmedEmail	CanNotify	Action
False	False	N/A	Send
False	True	N/A	Don't send
True	True	N/A	Send

Confirmation Email

EmailConfirmed	RequireConfirmedEmail	CanNotify	Action
False	False	N/A	Don't send
False	True	N/A	Send
True	True	N/A	N/A