Fix some style

src/main/java/be/cylab/java/wowa/training/SolutionDistance.java

@@ -2,8 +2,6 @@ package be.cylab.java.wowa.training;
 
 //import info.debatty.java.aggregation.WOWA;
 
-import org.jetbrains.annotations.NotNull;
-
 import java.util.Arrays;
 import java.util.List;
 
@@ -74,7 +72,7 @@ public class SolutionDistance implements Comparable<SolutionDistance> {
      * @return
      */
     @Override
-    public int compareTo(@NotNull final SolutionDistance solution) {
+    public int compareTo(final SolutionDistance solution) {
         return this.getDistance() > solution.getDistance() ? -1 : this.getDistance() < solution.getDistance() ? 1 : 0;
     }
 

src/main/java/be/cylab/java/wowa/training/Trainer.java

 package be.cylab.java.wowa.training;
 
-import org.jetbrains.annotations.Contract;
 
 import java.util.ArrayList;
 import java.util.Collections;