Include name of inviting XMPP user in MUC invitations to SMS numbers

[rozzin]

When people on the `SMS side' of the transport receive MUC invitations from XMPP users, it would be help with recognition and legitimization if a familiar `real name' was included in the the message and not just the initiating JID (if these people were really familiar with JIDs, they'd probably have a JID of their own and be receiving the invitation natively instead of via SMS).

Something like:

vcard name <jid> has invited you to join a group chat

Or, if a name is not available via vcard, something like:

"room nick" <jid> has invited you to join a group chat

(something similar to this latter form is already used in the case of SMS numbers inviting each other through cheogram, but when an XMPP JID issues an invitation currently only the JID is shown)