* Invoke hook when server starts
Invokes the `th-server-command-start` hook when the server is started, with the server object as the parameter. This allows adding a WebSocket listener to the server.
* Return the HTTP server from the listen function
Returns the node HTTP server created in the listen function to allow extension
* Add node HTTP server to server-command-start hook
* Change hook to post start in case we add a pre-start hook
* Create Hook__th-server-command-post-start.tid
