Add asset count to list

[bobpaul]

As a user, I'd like to be able to see the download status of my mods at a glance. I think adding a completed vs total asset count (c/T) to the output from the list command would certainly be nice.

this could maybe to an option, but I think it would be fine to always have this at the start of the line. It should have padding so all the names are still left justified.