Include ggdag?

[malcolmbarrett]

My package ggdag is a popular extension for dagitty to visualize and analyze causal DAGs. It would be great if you all would consider adding it to this list

[zeileis]

Imke @imkemayer, I think this is a good suggestion, would you consider updating the task view?

Also including the book project of Malcolm and his co-authors would be nice: https://www.r-causal.org/