Add support for file-based lists (keep following, keep muted, keep unmuted).

[Tyler-Darby]

I have added support for file-based lists for the "USERS_KEEP_FOLLOWING", "USERS_KEEP_MUTED", and "USERS_KEEP_UNMUTED" lists in the config file.

This makes for a less messy config file, and is overall easier to work with (especially when you may have a large amount of people that you are wanting to use here).

[Tyler-Darby]

I also added support for a counter for the auto_follow() function, in the format of "Now on number (x) of (y)"

Now, when following a large amount of people, you have a sense of how far in the program is.

[Tyler-Darby]

Also fixed a small typo.

[rhiever]

Pretty caught up with work and can't look at this now, but just wanted to let you know that I saw this PR and plan to get to it for review.

[Daviey]

Any chance this can land? Has been waiting over a year?

[rhiever]

Sorry, I'm not maintaining this library any more because it is not condoned by Twitter. Please feel free to fork it and continue maintenance separately.

[ermiyaeskandary]

@rhiever I am happy to take ownership of the repository and get working on the issues and tasks? Forking it can get lost - let me know?

https://www.linkedin.com/in/ermiya-eskandary/
https://twitter.com/ermiyaeskandary