commtrack domain-specific settings page (Case:52838)

Is the user-facing text good?  Also haven't hooked it up to any of the code where these values are currently hard-coded, should I do that?

![screenshot from 2013-05-20 16 40 29](https://f.cloud.github.com/assets/344026/538531/02554caa-c18e-11e2-8406-56f6e4a71573.png)