Don't perform page design check, when there are no themes in the site

[Alexander Obuhovich]

I recently worked on a project, with only Admin Console available and no themes at all.

I've tried to create some categories/sections and I wasn't able to do so, since error "Template - Can't inherit template from top category" was being displayed all the times. I wasn't able to select any alternative design template, since I haven't any theme created. 

Task: http://tracker.in-portal.org/view.php?id=1062

Ready for testing.

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Best Regards,

http://www.in-portal.com
http://www.alex-time.com