Multiple Configurator implementations loaded

[vbazhmin]

Hello, folks !

Thank you for a great work you've been doing for the past years :)

I'm very excited about 1.4.9 release. Is there a planned date available ?

Our team faced an issue when suddenly multiple Configurator instances started to load at once after we upgraded to 1.4.7.
https://github.com/qos-ch/logback/blob/master/logback-classic/src/main/java/ch/qos/logback/classic/util/ClassicEnvUtil.java#L52

Implementations are not expected to work at the same time. I've decided to create a workaround with Configurator.RankValue mechanism and Configurator.ExecutionStatus.DO_NOT_INVOKE_NEXT_IF_ANY for the first loaded Configurator.

Is it an expected way of configuring logback in runtime ? Or should it be configured differently with other logback mechanisms ?

Regards,
Vladimir