Fixed public list streaming

[shayanjm]

Fixes #164 - the issue was with the way list tweets were getting accessed. I added a new arg property args.filter_ids which takes a string of comma separated twitter IDs of users and leverages the streaming statuses/filter endpoint (https://dev.twitter.com/streaming/reference/post/statuses/filter) for efficient list streaming.

The default filter functionality in draw() is still used to limit the drawn tweets to exactly what you'd expect the list timeline to return (tweets/rts/replies by the members of the list, but not all tweets at them) - hence why both args.filter_ids and args.filter need to exist as arg properties. Could be made more concise by making args.filter a list of tuples (username, user_id), but the current implementation works.

[ghost]

@shayanjm Thanks! I have had problems with accessing public lists. I will test your changes.

[jcsackett]

I am currently running rainbowstream using the code from this PR and can confirm streaming a list with members I do not follow is working.

[jcsackett]

I've found an issue--it seems all tweets from members of the list are being shown. Including all replies. I'm unsure if this is a problem with the PR or if this is owing to some of the more obscure twitter api rules about when a mention/reply is and isn't supposed to be shown.