This is significant now because it will allow accurate recording of
multiple simultaneous connections.
This is important for the future because it establishes the
necessary infrastructure for recording downloaded sessions into their
own files so that they can be saved as backups.
Calling openConnection will return an open connection or nullptr.
Deleting the connection will close it.
SerialPort now uses this under the hood, while still presenting
the QSerialPort-compatible interface.
