[Bug #642] Material search form isn't working

The filter searches for materials which are enabled (disabled == false).
When a material is created its disabled field is NULL, so the search
fails.

It's necessary to updated table 'material' in DB:

UPDATE material SET disabled = false;

FEA: ItEr60S04ValidacionEProbasFuncionaisItEr59S04

navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/Material.java

@@ -41,7 +41,7 @@ public class Material extends IntegrationEntity implements Comparable {
 
     private UnitType unitType;
 
-    private Boolean disabled;
+    private Boolean disabled = Boolean.FALSE;
 
     private MaterialCategory category = null;