rft - stacktrace and raw btns in assertions as btn-group

To avoid situation with long assertions
![btns1](https://cloud.githubusercontent.com/assets/1964214/4272351/8109722c-3ce1-11e4-9fdb-b87bc7da88d4.png)

Now it always it top right corner as btn group
![btn2](https://cloud.githubusercontent.com/assets/1964214/4272362/947a8c92-3ce1-11e4-848d-d7aeaded6973.png)
![btn3](https://cloud.githubusercontent.com/assets/1964214/4272365/98832a88-3ce1-11e4-8483-ac6776bb5486.png)