Fix 'to' email address in email change confirmation email

Ghost User
2018-07-06T15:22:05+02:00

#### Previous behaviour
Steps to reproduce:

1. Change your email address
2. Both emails (confirm and verify) end up in the same inbox

#### New behaviour
Steps to validate that it works:

1. Change your email address
2. The emails (confirm and verify) end up in the right (different) inboxes