Cookbook Show UI adjustments:
- Adjust content padding around main and sidebar columns to match new design.
- Move owner and collaborators to top of sidebar.
- Move download button and stats to bottom of sidebar.
- Apply secondary button styling to sidebar buttons.
- Match knife command line box style to new design.
Remove 'cookbook' from sidebar title. Add readme typography formatting.
Merge pull request #305 from opscode/cookbook-show-ui-adjustments

Cookbook Show UI adjustments