Spotipy

Changed

- Updated the documentation to give more details on the authorization process and reflect
2020 Spotify Application jargon and practices.

- The local webserver is only started for localhost redirect_uri which specify a port,
i.e. it is started for `http://localhost:8080` or `http://127.0.0.1:8080`, not for `http://localhost`.

Fixed

- Issue where using `http://localhost` as redirect_uri would cause the authorization process to hang.

Fixed

- Fixed miscellaneous issues with parsing of callback URL

Added

- Support for shows/podcasts and episodes
- Added CONTRIBUTING.md

Changed

- Client retry logic has changed as it now uses urllib3's `Retry` in conjunction with requests `Session`
- The session is customizable as it allows for:
- status_forcelist
- retries
- status_retries
- backoff_factor
- Spin up a local webserver to autofill authentication URL
- Use session in SpotifyAuthBase
- Logging used instead of print statements

Fixed

- Close session when Spotipy object is unloaded
- Propagate refresh token error

Added

- Support for `add_to_queue`
- **Parameters:**
- track uri, id, or url
- device id. If None, then the active device is used.
- Add CHANGELOG and LICENSE to released package

Added

- Support `position_ms` optional parameter in `start_playback`
- Add `requests_timeout` parameter to authentication methods
- Make cache optional in `get_access_token`

Added

- Support for `playlist_cover_image`
- Support `after` and `before` parameter in `current_user_recently_played`
- CI for unit tests
- Automatic `token` refresh
- `auth_manager` and `oauth_manager` optional parameters added to `Spotify`'s init.
- Optional `username` parameter to be passed to `SpotifyOAuth`, to infer a `cache_path` automatically
- Optional `as_dict` parameter to control `SpotifyOAuth`'s `get_access_token` output type. However, this is going to be deprecated in the future, and the method will always return a token string
- Optional `show_dialog` parameter to be passed to `SpotifyOAuth`

Changed

- Both `SpotifyClientCredentials` and `SpotifyOAuth` inherit from a common `SpotifyAuthBase` which handles common parameters and logics.