- Added new config entry in mail config file called enable_debug

- If enable_debug is true then info about the mail are logged into the CI error logs
- Fixed queries to get sent and received messages with Recipient_model, now messages for which a notice email was not sent are retrieved and messages are sorted by insertamum
- CL/Messages_model:
	- Before setting a message as read check if a record is already present
	- If the recipient is a prestudent then in table tbl_msg_message oe_kurzbz is set with the ou of the prestudent
	- The sender id (person_id) now is get from the currently logged user also when replying
- MessageLib->_sendNoticeEmails checks that the message was sent only from FAS (NOT from infocenter)

application/config/mail.php

@@ -29,3 +29,6 @@ $config['wrapchars'] = 76; // Character count to wrap at.
 $config['mailtype'] = 'html'; // html or text
 $config['priority'] = 3; // Email Priority. 1 = highest. 5 = lowest. 3 = normal
 $config['validate'] = false; // If true then the email address will be validated
+
+// If enabled will be logged info about emails in Codeigniter error logs
+$config['enable_debug'] = false;