[feed] listing pages for new + popular apps (bug 957350)

![screen shot 2014-03-07 at 4 02 40 pm](https://f.cloud.github.com/assets/674727/2363775/fb4ad98c-a654-11e3-9c7f-f3fccf37264a.png)
![screen shot 2014-03-07 at 4 02 55 pm](https://f.cloud.github.com/assets/674727/2363778/039bf2e2-a655-11e3-9f7a-e9c86ac2eb5e.png)
![screen shot 2014-03-07 at 4 02 35 pm](https://f.cloud.github.com/assets/674727/2363776/fc04ea34-a654-11e3-9c09-5303d5804836.png)