⚡ ️ Improve Switcher.IO teardown
Fix problem where exiting Switcher.IO server using CTRL-C or SIGINT/SIGTERM signal does not properly exits. Also fix problem where executor child processes where not destroyed when exiting.
- Add Switcher::stop method to clean-up quiddities
- Add pySwitch::stop method to clean-up quiddities
- Move room name to constant
- Add on_shutdown aiohttp signal handler