This adds two modules to Skada:
AbilityTracker: Shows the last 10 abilities that a player has used and time between casts
AbilityBreakdown: Tracks personal ability usage and shows 1) time until an ability can be used again and 2) delay between when available and when used.
Module's primary purpose is as a post-combat diagnostic tool to see if you are using all your abilities to their maximum efficiency (if your class/spec revolves around cooldowns, e.g. hunters). Although you can also use it to spy on what folks are casting..