Improve admin LDAP user index

* Show which domain the current list is for
* Render text links as such

app/controllers/admin/ldap_users_controller.rb

@@ -4,11 +4,9 @@ class Admin::LdapUsersController < Admin::BaseController
   def index
     attributes = %w{dn cn uid mail admin}
     filter = Net::LDAP::Filter.eq("uid", "*")
-    if params[:ou]
-      treebase = "ou=#{params[:ou]},cn=users,dc=kosmos,dc=org"
-    else
-      treebase = "ou=kosmos.org,cn=users,dc=kosmos,dc=org"
-    end
+
+    @ou = params[:ou] || "kosmos.org"
+    treebase = "ou=#{@ou},cn=users,dc=kosmos,dc=org"
 
     entries = ldap_client.search(base: treebase, filter: filter, attributes: attributes)
     entries.sort_by! { |e| e.cn[0] }