basic framework for built-in web stuff on voicemail

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@6429 d0543943-73ff-0310-b7d9-9358b9ac24b2

conf/voicemail.tpl

 From: FreeSWITCH mod_voicemail <${voicemail_account}@${voicemail_domain}>
 To: <${voicemail_email}>
-Subject: ${voicemail_message_len} sec Voicemail from ${voicemail_caller_id_name} ${voicemail_caller_id_number}
+Subject: Voicemail from ${voicemail_caller_id_name} ${voicemail_caller_id_number} ${voicemail_message_len}
 X-Priority: ${voicemail_priority}
 X-Mailer: FreeSWITCH