change SimpleLogger implementation for slf4j for a more complete one

[MiniPlayer]

Currently we are using simpleLogger in root pom:
<dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-simple</artifactId> <version>${org.slf4j.version}</version> </dependency>

we should use a more complete logger, like "log4j" or " logback" . maybe an other ?

Imply to change every simplelogger.properties by correponding config file of new api.
But we could still use simpleLogger in test scope ?