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- slider items can link to other portal content using related items
(see ``imageslider_teaser_link_related`` in the README)
- pass image object to page-template too, so customized versions can use
plone.app.imaging scales if the want to.
- only show navigation if there are more than 1 images
- bugfix: images overlapped due to bug in circular implementation.
wrapping initialization with a timeout fixes the problem
- nicer layout for image captions using rgb() css transparency instead
of opacity (similar to newsitem_view)