Since using this library can be used as more than a native ruby logger, it's useful to allow log entries to capture log levels other than the ones that are used in Ruby itself.
In particular, this is for the fluent-plugin-graylog project, which is currently having to map log levels of alert, critical, and notice from incoming messages to other log levels to get them into Graylog via gelf-rb.
Since using this library can be used as more than a native ruby logger, it's useful to allow log entries to capture log levels other than the ones that are used in Ruby itself.
In particular, this is for the fluent-plugin-graylog project, which is currently having to map log levels of alert, critical, and notice from incoming messages to other log levels to get them into Graylog via gelf-rb.