BUGFIX: Content authors with SiteTree#canView() but not SiteTree#canEdit() were unable to click on SiteTree items in the CMS.
- The 'disabled' attribute in <li> will now only render if the author _really_ can't do _anything_
Merge pull request #754 from phptek/bug/073

BUGFIX: Content authors with SiteTree#canView() but not SiteTree#canEdit...