Server control command.
Puts the Qizx engine online or offline. When offline, the Qizx engine does not lock its XML Libraries, so they can be opened by another tool such as QizxStudio.
In GET or if command="status", simply returns the online status.
Note that this operation has nothing to do with stopping the server (Servlet Container) or the web app containing the Qizx server.
mime-type: text/plain
"online" if the server is up and running, "offline" otherwise.