Display server-initiated disconnect message

[jhalter]

This is low priority due to infrequent usage, but it'd be nice to add handling for the server-initiated disconnect transaction so that Hotline clients can see shutdown messages from the server admin.

In the original client this looks like:

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Hotline doc entry:

Disconnect Message (111)
Constant: myTran_DisconnectMsg
Initiator: Server

Receive disconnect message from the server. Upon receiving this transaction, client should close the connection with server.

Fields used in the request:

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