Youtube-transcript-api

Changes:

- added `list_transcripts(video_id)` to `YouTubeTranscriptApi`, which returns a `TranscriptList` object, representing all available transcripts
- `TranscriptList` objects provide the methods `find_transcript(languages)`, `find_generated_transcript(languages)` and `find_manually_created_transcript(languages)`, which return `Transcript` objects
- `Transcript` objects represent a transcripts and provide metadata properties
- by calling `transcript.fetch()` the actual transcript is fetched
- added new translation feature
- by calling `transcript.translate('de')` on a `Transcript` object YouTubes translation feature can be accessed
- added more specific exception types and thereby vastly improved error messages
- `TranscriptsDisabled`, `NoTranscriptFound`, `VideoUnavailable`, `NotTranslatable`, `TranslationLanguageNotAvailable`, `NoTranscriptAvailable`
- all exceptions are subtypes of `CouldNotRetrieveTranscript`
- updated CLI to make new features accessible
- updated Documentation to explain new features and changes
- completely reworked how the module scrapes transcripts, which makes it way more solid

BREAKING:
- `youtube_transcript_api.YouTubeTranscriptApi.CouldNotRetrieveTranscript` has been move to `youtube_transcript_api.CouldNotRetrieveTranscript`

Special thanks to danielcliu for his contributions and time in the reviewing process!

It turned out that the the changes in v0.1.8 were still missing some details, which only occurred under certain circumstances. This has been fixed in this version.

A change in the YouTube webclient did completely break this module. This is fixed as of this version.

A Bug was fixed which caused the API to crash on empty subtitles boxes.

The `YouTubeTranscriptApi` no longer logs errors in the `get_transcript` method. This way the user of the API can control wether an error should be logged or not.

The error message which is shown when an `CouldNotRetrieveTranscript` Exception is raised, now is more specific on what the cause could be.