Multiple items support for autoheight plugin

Demo
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before: http://dimmy.pro/autoheight/before/
after: http://dimmy.pro/autoheight/after/

Screenshots
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before: http://my.jetscreenshot.com/7945/20141027-3g7l-156kb.jpg
after: http://my.jetscreenshot.com/7945/20141027-zwin-181kb.jpg