K1 turtle: add dots every 50px

- Change dropdown images to include dots

![image](https://cloud.githubusercontent.com/assets/206973/3771638/1fff3d1c-18f7-11e4-85de-35e92edb921d.png)

![image](https://cloud.githubusercontent.com/assets/206973/3771651/3cb8eb1a-18f7-11e4-967a-63b50bde5f56.png)