Speed up index view

This improves the response time of the index view a whole chunk (about 5x). It also reduces the severity of a memory leak.

![contacts-memory-usage](https://cloud.githubusercontent.com/assets/74812/2818560/97cee1c8-cee5-11e3-8b47-eafe3ac18dda.png)

The first box shows the impact of sending 400 requests for the index page to `frontend-1`. The second box shows the impact of sending 2000 requests to the same machine. The requests were sent using curl and a bash loop, as fast as a single worker could process them.