Main_start instances unable to start/stop gracefully

[myrakrusemark]

Main_start instances are subprocesses that require running self.main() to start, and self.close() to stop.

2/3 available plugins (Daisy, Noaa) have been observed to start/stop gracefully. The issue seems to be in main.py.

I think main.py is looking for instances added to hook_instances["Main_start"], and should instead be looking at whether available_module says its enabled, then main/close the module accordingly.

[myrakrusemark]

A lot of work done in this direction but not tested.
Final implementation will utilize self.close()