Better support for anonymous invitations

With the new message preview it is far more obvious that anonymous invitations (ie. allowing anonymous users to send invites) need some adjustments. Anonymous users neither have a name nor an email address associated with them, which looks ugly when using the corresponding tokens in the sender name, subject line and message body.

One idea would providing more (optionally) editable fields, just like the email subject. This works for the sender name and the From email address (the latter would only be editable for anonymous users), but the message body would need to be duplicated (ie. needs a different template using less tokens).

If you any other or better ideas please post them here.
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Stefan Kudwien
_{unleashed mind}