Ceylon.logging

Looging module which provides integration with Java modules (xnio, netty) and ceylon java runtime itself.
Integration uses JBossLogManager, which can integrate with different Java logging libraries (log4j, slf4j, jul).

There are still some issues, while `../ceylon-dist/dist/bin/ceylon run --run test.ceylon.logging.run test.ceylon.logging/0.6` works,
`ant test-jvm` fails because of ClassCastException (looged as: IllegalStateException: The LogManager was not properly installed).
Where could this difference come from ?

Logging module is still basic, please give me some comments on integration and Ceylon API.

This pull request requires:
https://github.com/ceylon/ceylon-compiler/pull/1178
https://github.com/ceylon/ceylon-runtime/pull/39