chore(list): list plugins by last_action - most recent version upload

Fixes #56 

This really makes the bottom lists look much less stale
![screen shot 2014-11-25 at 2 11 08 am](https://cloud.githubusercontent.com/assets/738363/5181194/f9d14150-7448-11e4-9923-afa64b0362be.png)