adds blacklight_range_limit plugin to app
adds adv search int tests related to date and adds date range to advanced search
adds shim for ie8 support and overwrites unneeded helper method
overwrites helper method which enables parameter keys to be deleted
WIP on embed browse plugin
updates plugin to work with preview and limits the amount of previous/next a user can click through
updates plugin to toggle browse viewers
Merge pull request #329 from sul-dlss/range-limit

Adds range limit plugin
Merge pull request #325 from sul-dlss/embed-browse

Embed browse plugin
Move thumbnail controller method into a concern that can be included in multiple places.
Support object specific thumbnail partials to differentiate between catalog and repository items.
Remove alt on cover/stacks images and add a tabindex of -1.