Mute sub-Task-Kensho updates

A fix to mute sub-distros of Task-Kensho group of distros, since Task-Kensho would likely be uploaded at the same time any way.

Below is a screenshot of how the Task-Kensho updates currently show up in channel:

![9i6ifcl](https://f.cloud.github.com/assets/5747918/1970721/2b8682a6-8312-11e3-8b41-b1502fca1861.png)