Smartdown previous answers grouping

Previous answers block in smartdown now looks like this: 

![previous answers block](https://cloud.githubusercontent.com/assets/3466862/4386876/9af36f9e-43d5-11e4-821e-ae2b22d56a69.png)

- Using govspeak table layout instead of ordered list now.
- Additional partials created for smartdown specific collapsed question and previous answer views.

https://www.agileplannerapp.com/boards/105200/cards/5834
This can be done on a single line:
```
<%= question_page.title unless question_page.title.blank? %>
```