Formats long text in navigation prompt.

Addresses second part of https://trello.com/c/VXElEL4E/128-padding. Separate PR coming for overall app padding.

![device-2014-02-20-111044](https://f.cloud.github.com/assets/464123/2220082/9790d322-9a49-11e3-89d4-c5e99d8c6746.png)