Lithium beta 2: Confirm LiteCore request for close, before connection is opened.

If a remote does not respond to a request to open a connection it will time out and LiteCore will request that the connection be closed.
When it times out, the platform fails to confirm, to LiteCore, that the connection has been closed.  Need to determine whether the confirmation is required and, if it is, make sure it happens.

As an associated issue, at the moment, we ignore all subsequent activity from the connection.  In particular, we ignore a delayed open from the remote, after the connection has been closed.  We might be able to do better.