Bug 213126 Add support for DataEngine-leve dataset cache
In many cases the DataEngine-leve dataset cache is useful which ensure that a dataset is executed one time during rendering one report. To support this feature a new dataset property should be added. The Birt customer can choose whether this dataset need to be cached or not by setting the property in deisgn time.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/writer/ModuleWriter.java
writer.endElement( );
			}
			writer.endElement( );
		}
	}
	/**
	 * Writes the contents of the container information. The contents are
	 * enclosed in an optional list tag.
	 * 
	 * @param containerInfor
	 *            the container infor
	 * @param tag
	 *            the optional list tag that encloses the list of contents
	 */
	private void writeContents( ContainerContext containerInfor, String tag )
	{
		assert containerInfor != null;
		List list = containerInfor.getContents( getModule( ) );
		if ( list.isEmpty( ) )
			return;
		
		DesignElement tmpElement = containerInfor.getElement( );
		if ( tmpElement.getExtendsElement( ) != null )
		{
			PropertyDefn propDefn = tmpElement.getPropertyDefn( containerInfor
					.getPropertyName( ) );
			if ( propDefn == null
					|| propDefn.getTypeCode( ) != IPropertyType.CONTENT_ELEMENT_TYPE )
				return;
		}