ceylogback

Configure ceylon.logging to use Logback as backend. (JVM runtime only, obviously.)

• Your project must be run with a flat classpath. (Info about how using Logback without flat classpath would be welcome!)
• You must use the JVM parameter -Dceylon.include.slf4j (at least for Ceylon 1.3.2).
• Call the toplevel function configureLogbackLogging().
• Normal Logback configuration (logback.xml etc.) will take place---put your logback.xml into your project's resource/your/project/ROOT directory.
• You can now obtain loggers using Logback from the ceylon.logging::logger(Category) function.
• Logger names will have a P or M prefixed if they're package or module loggers (maybe disputable).
• Your Ceylon loggers will have a priority according to the Logback configuration, and you can assign it a new value.
• This will get out of sync when you modify the level of the Logback loggers directly or change a configuration file that is tracked by the Logback configurator.

Levels are mapped to Priorities with the same names, FATAL is mapped to ERROR with a "FATAL: " message prefix, and ALL and NONE cannot be used.