Reordering jmetal package structure
Renaming _main classes to Runner
Refactoring XReal and related classes
Still workgin with XReal
Reorganizing packages
Refactoring XInt
Finished RealSolutionTypeTest
Added src/main/java/org/uma/jmetal/util/ExtractParetoFrontAndDecisionVariables.java
Refactoring ExtractParetoFrontAndDecisionVariables.java
Refactoring ExtractParetoFrontAndDecisionVariables.java
Added template for src/test/java/org/uma/test/util/ExtractParetoFrontAndDecisionVariablesTest.java
Adding new features to SolutionSetOutput