Bdm users can view post histories

https://trello.com/c/VIDYdZzA/14-as-a-user-i-can-see-all-of-my-posts

![image](https://cloud.githubusercontent.com/assets/8669803/4925722/48132de0-652d-11e4-88d7-e7f33b9adf7a.png)

``` erb
<%= link_to current_user.email, current_user %>
```