DDBNEXT-103: refactor

  - add id for pagination
  - use id instead of class for institution-list
DDBNEXT-103: update index on sector select/unselect.
DDBNEXT-95 replace jQuery.show and hide with css.

  jQuery show() and hide() is slow for a lot of elements.
  SEE:
  http://www.learningjquery.com/2010/05/now-you-see-me-showhide-performance
ddbnext-103: wip
DDBNEXT-103: add number to index/pagination
DDBNEXT-103: cache all list items.
DDBNEXT-103 refactor, add console.log
DDBNEXT-103: fix self-updating first character index and show message
DDBNEXT-103: show visible
DDBNEXT-103: select by sector does not work anymore.
DDBNEXT-103: caching is broken
DDBNEXT-103: refactor
DDBNEXT-103: handle empty hash
DDBNEXT-103: make pagination smaller.
DDBNEXT-103: Only execute the script in institution list page.
DDBNEXT-103: remove all console.log
Merge branch 'feature/ddbnext-103' into develop

Conflicts:
	grails-app/controllers/de/ddb/next/ItemController.groovy