TrackID is always prepended to the logstring

New logging options in config-template.php

Possible to configure logging to use syslog or file

Please test the new logging function. 

Logging handler has only been added. The old logging function is still uses in the code. 

After test all logging calls should be rewritten to the new format.

Usage:

Required:

require_once('SimpleSAML/Logger.php');

Logging:

Logger::emergency("text to log");
Logger::critical("text to log");
Logger::alert("text to log");
Logger::error("text to log");
Logger::warning("text to log");
Logger::notice("text to log");
Logger::info("text to log");
Logger::debug("text to log");
Logger::emergency("text to log");

Logger::info(array("text","to","log"));

Statistics:
Stats are prepended with STAT in the logfile for easier analysis.

Logger::stats("SSO");

Example (syslog): 
Feb  7 21:02:33 server_name simpleSAMLphp[pid]: [trackid] loglevel text to log

git-svn-id: https://simplesamlphp.googlecode.com/svn/trunk@268 44740490-163a-0410-bde0-09ae8108e29a