Syslog support

You can configure logging to use syslog instead of rolling file. You can
use type option for this purpose. Nothing extra is needed but note that
syslog has it's own severity filtering.

Syslog facility daemon is being used. Ident is set to katello (or
delayed_katello for delayed job)
Support for log trace

You can set log trace feature in logging configuratio now which will add
an extra line to every log message that displays from which file:line
and method was this message logged.

This also implies all loggers must be named in configuration. When you
add a new logger somewhere in code you must mention it in configuration
otherwise log trace feature won't work for this logger.