This plug-in will be started after FITSManager-Core, and won't be manage in
FITSManager-Core's Plug-ins Control module.
Since there are potential deadlock when FITSManager's whole application
starting(if FITSManager-Core doesn't active, and other plug-ins want to get
resource from FITSManager-Core at the same time, it will be deadlock), this
plug-in's works after FITSManager-Core active.