Discord-oauth2-py

I rewrote the library and uploaded it a pypi!!!

added a new function for client_credentails_grant which will generate an AccessToken for the owners account and much more. I'll update the README.md in a moment.

This should automatically trigger a workflow to publish the library onto pypi if im not mistaken.

happy coding!

- Added `webhook` property to `access_token`, will be a [webhook object](https://discord.com/developers/docs/resources/webhook#webhook-object) if the `webhook` scope is provided otherwise it will be `None`.
- Added `guild` property to `access_token`, will be a [guild object](https://discord.com/developers/docs/resources/guild#guild-object) that the bot joined if the `bot` scope was provided otherwise it will be `None`
- `Exception` is raised if an HTTP error occurs in `discordoauth2.exchange_code` or `discordoauth2.refresh_token`

_No code should break this release, but it may next release._

- Added `guilds.members.read` support
- Added `refresh_token()`, the ability to refresh an access token.
- Removed `gdm.join` as it is no longer supported by discord
- **`exchange_code()` now returns a `access_token` object.** (this will break all code using an older version)

Access tokens have three properties:
- `access`: `token_instance` object (`exchange_code()` used to return a `token_instance` object)
- `expires`: how many seconds until `access` will expire.
- `refresh_token`: this can be used with `refresh_token()` once `access` has expired

Changed core structure to use classes instead. Code much cleaner.

First build, this was created a month ago but publishing today. It works but the code is clunky.