Remove no needed method on interface.

There is no need to have defined in the interface a init method in
order to apply post creation callback

FEA: ItEr60S04ValidacionEProbasFuncionaisItEr59S04

navalplanner-webapp/src/main/java/org/navalplanner/web/common/components/finders/IMultipleFiltersFinder.java

@@ -31,8 +31,6 @@ import org.zkoss.zul.ListitemRenderer;
 
 public interface IMultipleFiltersFinder {
 
-    void init();
-
     /**
      * Return the FilterPair list match with filter.
      * @param filter

navalplanner-webapp/src/main/java/org/navalplanner/web/common/components/finders/ResourcesMultipleFiltersFinder.java

@@ -46,7 +46,6 @@ public class ResourcesMultipleFiltersFinder extends MultipleFiltersFinder {
     protected ResourcesMultipleFiltersFinder() {
     }
 
-    @Override
     public void init() {
     }