Make the UNLchat intro text less awkward

Right now on top level pages the, UNLchat says 'CHAT WITH WELCOME TO NEBRASKA', this changes it so that it says 'CHAT WITH UNL'.  The 'Welcome to nebraska' bit was awkward.

sharedcode/localSiteLinks.html

 
 <link rel="home" href="http://www.unl.edu/" title="UNL" />
+
+<script src="/ucomm/sharedcode/scripts/top_level.js"></script>

sharedcode/scripts/top_level.js

+
+// Set the site title for TOP level sites so that the intro text is nicer (and the site title changes)
+var visitorchat_config = {
+	'site_title' : 'UNL'
+};