Move to Quart and quart-discord; uses async

[thrzl]

I also moved over to the Quart framework and quart-discord, which makes it a lot easier to create and use Discord OAuth2 Flows. I also added comments and formatted the code in a better way.

What's next on this fork

Next I'll bring in discord-ext-ipc to better interface with the bot. This will allow us to use our bot almost as a REST API, and therefore allow the webserver to work with better integration with the bot.

[thrzl]

In commit f5e1d8d3ff65fd136fe953088f99e8815fd57e40, I accidentally merged two changes

I not only removed the OAuth file import, but I added quart-discord support.