Add util.log.LogConfiguration

[thekid]

See #11 (comment)

Configuration

[default]
uses=console|syslog|files

[console]
class=util.log.ConsoleAppender
level=ALL

[files]
class=util.log.FileAppender
args="/var/log/server.log"
level=ALL

[syslog]
class=util.log.SyslogUdpAppender
args=127.0.0.1|514|server
level=WARN|ERROR

API

$c= new LogConfiguration(new Properties('log.ini'));
$cat= $c->category('default');   // Returns console, syslog and files
$cat= $c->category('syslog');    // An appender as configured by "syslog"

$all= $c->categories();  // ["default" => new LogCategory()->withAppenders(...), "syslog" => ...

$name= 'does-not-exist';
$exists= $c->provides($name);    // FALSE
$cat= $c->category($name);       // ***lang.IllegalArgumentException***

Migration

- $l= Logger::getInstance();
- $l->configure(new Properties('log.ini'));
- $cat= $l->getCategory('default');
+ $c= new LogConfiguration(new Properties('log.ini'));
+ $cat= $c->category('default');