This PR adds a launcher for V3.
Features:
* Starting Red (with or without autorestart)
- Lists available instances on the spot and has the user select one to be used
* Updating Red (though only what is on PyPI atm)
* Instance creation (using redbot-setup via an import) (requested in #850)
* Some basic debug info (Python version, Red version, OS version/arch, user who ran the bot) (as requested in #850)
Obviously there's some improvements to be made still but this is a starting point for an actual launcher
该提问来源于开源项目：Cog-Creators/Red-DiscordBot
