Fix bug in material creation.

The error only happened the first time the application is launched. In
the next executions the UnitType would already be in the database so
it's not transient. Calling dontPoseAsTransientAnymore so this doesn't
happen.

FEA: ItEr60S04ValidacionEProbasFuncionaisItEr59S04

navalplanner-business/src/main/java/org/navalplanner/business/materials/bootstrap/UnitTypeBootstrap.java

@@ -65,6 +65,9 @@ public class UnitTypeBootstrap implements IDataBootstrap {
     }
 
     public static UnitType getDefaultUnitType() {
+        if (defaultUnitType.isNewObject()) {
+            defaultUnitType.dontPoseAsTransientObjectAnymore();
+        }
         return defaultUnitType;
     }
 }