remove opening and closeing events from key events panel

Remove 'Latest Post' and 'Opening post' from live blog key events panel ( The two events indicated in the before ) 

Before:
![with-latest](https://cloud.githubusercontent.com/assets/986155/4355921/e91ddac6-4252-11e4-80c1-e5ece3439e95.png)


After:

![no-latest](https://cloud.githubusercontent.com/assets/986155/4355913/c53d7a94-4252-11e4-8ad3-1ddaa52d9b65.png)