* Move the xlat function to a separate file in lib/xlat.php3

* Move the xlat function to a separate file in lib/xlat.php3
* Add a lib/sql/nas_list.php3 to also get the nas list from sql (naslist.conf still works)
* add realms nasdb and nasadmin in username.mappings. nasadmin is used to signify if the
  user is allowed to use the nas_admin page. nasdb is used to shorten the nas list to only
  a few specific entries. That way administrator responsible for a few access servers will
  only be able to administer those access servers and not see the rest of the nas list.
* Add username searching in the find page as suggested by joram agten
* Don't use nas_list in nas_admin