Added some rails specific rules

Before: 
![before](https://cloud.githubusercontent.com/assets/1380672/5449666/6e33401e-84ae-11e4-85fd-7b0ea41f5324.png)

After:
![after](https://cloud.githubusercontent.com/assets/1380672/5449665/6e334c80-84ae-11e4-80a1-77aa8bc5f2e6.png)