Add a Challenges section for additional types of practice while macro'ing

[bsaffel]

Example Challenges:

• worker stacking
• scouting
• defend harassment
• double/triple pronged attack by X time
• constant army movement (posturing)

[bsaffel]

A Challenges section that gives you in-game mini-objectives to complete apart from the supply and build order objectives. Some thoughts are that:

• you will probably need a couple of unique or custom UI elements to display the various time or objective displays that do not rely on the main or secondary objectives provided by blizzard.
• Is it possible to create an tertiary objectives window somehow or is the game locked to just the two.
• How popular would Benchmarker have to get for Blizz to add it for me :)