Add support for https://unacademy.com/

[ramjmi]

Checklist

• I'm reporting a new site support request
• I've verified that I'm running youtube-dl version 2019.05.11
• I've checked that all provided URLs are alive and playable in a browser
• I've checked that none of provided URLs violate any copyrights
• I've searched the bugtracker for similar site support requests including closed ones

Example URLs

• Single video: https://www.youtube.com/watch?v=BaW_jenozKc
• Single video: https://youtu.be/BaW_jenozKc
• Playlist: https://www.youtube.com/playlist?list=PL4lCao7KL_QFVb7Iudeipvc2BCavECqzc

Description

WRITE DESCRIPTION HERE
This is an educational website. I need to download videos from this.
Thanks

[ramjmi]

Sir/Madam
Plz provide the youtube-dl support for the site https://unacademy.com/. I am unable to download playlist from this. Also, site provides download option to its android app. Support for this site is not helping me only but thousands of students in their learning.
link:
https://unacademy.com/lesson/absolute-value-and-polar-form-of-complex-numbers-in-hindi/1ORM5SAI/?source=Course