Alert banner #1218
Description
Add ability to configure an alert banner that will show up on item and/or search results pages. Temporarily hacked this in by adding the following into base.html after the header block include:
<div class="span12"><div class="alert"><div class="text-center"><font color="#8d321a"><strong>A significant number of ebooks will be unavailable on Saturday, January 20 from 1-7pm due to vendor maintenance.</strong></font></div></div></div>