implement player stats

[idougherty]

• height
• weight: should impact both player mass & rotational "stiffness"
• arm length
• speed
• jump height
• speed with ball
• power

[idougherty]

we should think about combos that players would want to make

shooting: jump height, power, weight (helps accuracy), & maybe arm length athletic: speed, speed with ball, arm length, jump height big: height, weight, arm length