Customize log level names

[florensie]

trafficstars

It would be nice to be able to customize the log level names. Logging libraries across different languages will often use different names for log levels. Eg. "Verbose" instead of "TRACE", or "Information" instead of "INFO".

For implementation, for the logback encoder I suggest a protected method that takes a log level and is allowed to return any string. I have not looked at possible solutions for the other supported logging libraries.