Show only selected branch

Show all branches by default.

![filter_ref_1](https://f.cloud.github.com/assets/72138/377944/858cb7e4-a504-11e2-8c14-df892b4688da.png)

Show only selected branch if checkbox is checked.

![filter_ref_2](https://f.cloud.github.com/assets/72138/377947/90f4d904-a504-11e2-9e93-e869998b4d67.png)