Potential memory leak

[achingbrain]

The trackConn function in the listener stores each maConn in the __connections array on the server, in order to close them when the listener is closed.

close is an async method so there could be an unhandledPromiseRejection here, but that's a separate issue.

It doesn't ever seem to remove them from the array. We should be working out if the MaConn is closed at any point - then we can remove them from the list since it won't be necessary to close them when the listener is stopped.