remove needless div.container

fix content overflow at workflow tab:

![bildschirmfoto 2014-05-31 um 22 30 24](https://cloud.githubusercontent.com/assets/2835032/3140053/a0a1943a-e902-11e3-9889-0e704a26d9fa.png)

without container:

![bildschirmfoto 2014-05-31 um 22 33 03](https://cloud.githubusercontent.com/assets/2835032/3140057/d89f47a6-e902-11e3-987f-f91271340601.png)