* Added an exception clause that catches `FileNotFoundError` and logs a debug message in `SpotifyOAuth.get_cached_token`, `SpotifyPKCE.get_cached_token` and `SpotifyImplicitGrant.get_cached_token`.
* Changed docs for `auth` parameter of `Spotify.init` to `access token` instead of `authorization token`. In issue #599, a user confused the access token with the authorization code.
* Updated CHANGELOG.md
* Removed `FileNotFoundError` because it does not exist in python 2.7 (*sigh*) and replaced it with a call to `os.path.exists`.
* Replaced ` os.path.exists` with `error.errno == errno.ENOENT` to supress errors when the cache file does not exist.
