Added the ability to do an authenticated SMTP login to send mail.

Added the ability to do an authenticated SMTP login to send mail.

  * by setting the array variable '$wgSMTP' in Local settings,
    the source will use PEAR:mail to connect to a specific
    SMTP server to send mail. It will use an authenticated
    login, if requested.

  * Example:

    $wgSMTP = array (  "host" => "smtp.wherever.com",\r                       "IDHost" => "mail.wikipedia.org",\r                       "port" => "25",\r                       "auth" => true,\r                       "username" => "mailID",\r                       "password" => "mailPswd");