* include/functions_ui.php: Added get_url_refresh which gets the correct
url to refresh a page against instead of manually reconstructing for each
form. Modified process_page_head to use this new function
* general/header.php: Use of new function get_url_refresh. Fixes some
minor annoyances I had with this refresh when groups were selected with
a post
* ajax.php: Error message didn't display the right page name
* operation/agentes/estado_agente.php: Fixed bug #2770377
git-svn-id: https://svn.code.sf.net/p/pandora/code/trunk@1640 c3f86ba8-e40f-0410-aaad-9ba5e7f4b01f