Captiveportal_clean_dn_database function added and other changes in the functions that relate to radius

Captiveportal_clean_dn_database function added and other changes in the functions that relate to radius.

On line 1204 "if (is_null($pipeno)) {" replaced for "if (empty($pipeno)) {". Pineno takes value 0 if there are no free pipes, is_null would return false instead of true in case it is 0

I guess there is an error in the function portal_mac_radius specifically below the following condition:

if (! empty ($ auth_list ['url_redirection']))
portal_reply_page ($ auth_list ['url_redirection'], "redir");
     return FALSE;

This line (return FALSE;) appears at the end of the function so the function never returns TRUE but FALSE always, based on the following:

When using if statements without the curly braces, remember than only one statement will be Executed as part of That condition. If you want to place multiple statements you must use curly braces, and not just put them on the same line.