1.6 released

Use Netbeans 12.5 for the development
Use docJGenerator 1.6.5.8
Use jDependency 1.4.6.3
Use JEditor 1.2.15
Use Groovy 4.0.16
Use Rhino 1.7.14
Use JRuby 9.4.5.0
Update the JRuby wrapper to replace the "import" by the "java_import" declaration to take into account changes on JRuby 9.4