LogTarget is a class to encapsulate outputting LogEvent's.
This provides the base for all output and filter targets.
Warning: If performance becomes a problem then this
interface will be rewritten as a abstract class.
author: Peter Donald
Process a log event.
In NO case should this method ever throw an exception/error.
The reason is that logging is usually added for debugging/auditing
purposes and it would be unnaceptable to have your debugging
code cause more errors.
Parameters: event - the event