Ahsoka Tano rework.

I use Ahsoka in my top 20 arena squad. I personally love her. For people complaining about her taking critical hits and losing her bonuses, use crit avoidance mods. I'm pretty sure they were made exclusively for her, and they make more sense than speed for her. If she doesn't take the crits, she has +45 speed, the most you'll get from a speed mod is roughly 32, I think. And her group heal, while not much, does come in handy, especially for Anakin, as it boosts others over 50% health, and giving him more attacks in the long run.