Fixing he CSS.
Start working on the ajax pulling.
Pulling via AJAX.
Adding an API function for the checkout command.
Rename the function and hide the update button.
Merge pull request #5148 from openscholar/5115-ajax-pull

Pull sub-themes via Ajax
Merge branch 'SCHOLAR-3.x' into 4373-handling-errors
Bring back the X-Generator vlidation.