[enhancement] Request features for members

[fu-raz]

First off, this package is exactly what I'm looking for. I've been working on a nodejs YouTube chatbot for my live streams and I've been using the YT API. Which has a lot of negatives. It's slow, limited to 10000 API calls per day and lacks the SRC for SuperStickers.

This package is almost perfect, I just miss a few things for members.

YouTube has two events that I don't see in your YouTube-Chat package, which are 'new member' and 'member milestone'. I would love to have the details for these as well.

New member has no real details aside from level (maybe if it's a level upgrade)

Member milestones include the amount of months the member has been a member and also a text/comment from the user

Also a little side note, I would call 'isMembership' -> 'isMember'. All the other properties can be read as 'user is owner', 'user is verified', 'user is moderator', but only 'user is membership' semantically this should have been 'user HAS membership' or 'user is member'.