201a3990 

Add a type for `Dependencies`

It’s just a `Map`, but it gets used often enough that it makes sense.
Time to Start Worker time Duration Time to finish
Config 0s 1s 1s 2s
Eval 3s 6s 6s 9s
Build 10s 1m13s 1m17s 1m28s
Suite 0s 1m21s 1m27s 1m28s