Replace Logger with SLF4J logging framework

[abranson]

The internal logging system should be able to push its log messages to the standard java log framework.

[kovax]

I would recommend to replace the cristal logging with a standard java
library like SLF4J or Logback:

http://logback.qos.ch/
http://www.slf4j.org/

[kovax]

• Make org.cristalise.kernel.utils.Logger deprecated.
  Keep the class for dependent projects and Scripts to use it.
• Replace all occurrence of org.cristalise.kernel.utils.Logger using Lombok @slf4j
  • kernel
  • jooqdb
  • restapi
  • xpath-outcome-initiator
  • dsl
  • dev
  • testing
  • trigger
  • in-memory-lookup
  • gui
  • lookup-ldap
  • xmldb

[kovax]

Perhaps the better choice would be to use Google's Fluent Logger:
https://google.github.io/flogger

Text copied from webstie:

Benefits
While some users prefer “fluency” as a style, this is not what the argument for Flogger rests on. Flogger offers these key, concrete advantages over other logging APIs:

Logging at disabled levels is effectively free. Finally, you can add as many fine-grained log statements to your code as you want, without worry.
Flogger also has very high performance for enabled log statements.
A fluent API accommodates a variety of present and future features without combinatorial explosion, and without requiring separate logging façades.
Less reliance on long parameter lists makes it harder to misuse and yields more self-documenting code.