User can add a stop

https://trello.com/c/SGlx7dDb/42-as-a-user-i-can-add-a-stop

![screen shot 2014-11-19 at 10 08 12 am](https://cloud.githubusercontent.com/assets/3759510/5107942/fe2047c0-6fd3-11e4-92e1-faa5813bb5c5.png)