Implement tracker reaction images

[MattEqualsCoder]

I won't be able to go through any time soon and really find good lines for this, but I'm going ahead and implementing this. This allows you to change the images that are used for tracker. Currently there are three reactions: default, WTF, and bored. Once tracker finishes saying a line, she'll reset back to the default.

It's usable like this in the configs, and the TrackerImage values shouldn't be case sensitive.

- Text: <break time='3s'/> Oh I'm sorry. Was I supposed to care about Reserve Tanks?
  Weight: 0.5
  TrackerImage: Bored

Apparently I accidentally committed to the config main branch directly. 😬 Here's the commit for the config branch