Bug 201368 Support "Not In" operator in filter list
Description: After we support "IN" filter we should also support the "Not In" filter. Data part has already support the "Not In" filter, so hope model can support that operator in the filter operator list. Regards!
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ModuleUtil.java
if ( existedElement == null )
				return true;
			return false;
		}
		catch ( PropertyValueException e )
		{
			return false;
		}
	}
	/**
	 * checks is the name value is valid for the design element.
	 * 
	 * @param elementHandle
	 *            element need to be checked for the name.
	 * @param nameValue
	 *            name of the element.
	 * @return true if the name is valid, false if the name is not valid.
	 */
	public static boolean isValidElementName( DesignElementHandle elementHandle )
	{
		return isValidElementName( elementHandle,
				IDesignElementModel.NAME_PROP,
				elementHandle.getName( ) );
	}
	/**
	 * Determine if the value1 of this filter condition is a list.
	 * 
	 * @param filter
	 *            the filter need to check
	 * @return true if the value1 value is a list, false if it is a single