Added strategies.

Strategy identification is pretty primitive.  Right now it is just what
units their army was comprised of at a given time.  This could be combined
with APM, resource gathering rates, supply capped time, and upgrades to
give a pretty good overall strategy & competency perspective, I think.

Add in a couple other minor features like Bunkers built and Sensor towers
built and you'd have a half decent learner, I hope.