Improve Essentials UI on small screens

Using Essentials on a small screen results in the following issues.
On small devices

• The documentation link must be underneath the changes made list instead of right on the same line
• The Install button must be under the the header instead of right on the same line
• The rebuild link must be in the navigation menu, not in the toolbar
• Messages must not overlap the navigation menu. Shortened with ellipses ...
• Preference to close the navigation menu when clicking outside the menu

https://docs.google.com/a/1hippo.com/file/d/0B8WSFIxqRjFoSmxkTGZyenJmXzA/edit