Added more attributes and methods to Anime class and renamed classes

This release comes with a lot of changes.

Anime class changes:

• Added is_nsfw() method
• Added type, status, producers, genres and teaser attributes
• Fixed more encoding errors

General changes:

• Renamed anime to Anime
• Renamed aninews to Aninews
• Renamed charsearch to Charsearch
• Renamed anilyrics to Anilyrics
• Reformed gs.py (which is now called helpers.py)

See the docs at https://animec.readthedocs.io/en/latest/ for more info!