Configure Email functionality

In order to successfully create a mailbox and/or forwarders-only the following settings must be configured:

1. An 'Email' role must have been installed on a server
2. The website must be assigned an 'Email' role
3. A Roundcube domain must be configured in 'Settings' > Platform' > 'Platform domains' > 'Roundcube domain'
4. The customer's hosting package must allow 'Email accounts'