Bug 179674 Support time dimension in model
When define time dimension in model, the "itTime" property will be set. However this is not enough. We also need to know to what precision the time value should be evaluated, say, year, month, day, etc. Model needs to be enhanced to support such requirement.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/writer/ModuleWriter.java
* @param obj
	 *            the element that has the property
	 * @param attr
	 *            the XML attribute name
	 * @param propName
	 *            the name of the property to write
	 */
	protected void attribute( DesignElement obj, String attr, String propName )
	{
		ElementPropertyDefn prop = obj.getPropertyDefn( propName );
		assert prop != null;
		Object value = obj.getLocalProperty( getModule( ), prop );
		if ( value == null )
			return;
		String xml = prop.getXmlValue( getModule( ), value );
		if ( xml == null )
			return;
		writer.attribute( attr, xml );
	}
	/**
	 * Writes one property entry of an element.
	 * 
	 * @param obj
	 *            the design element
	 * @param propName
	 *            the property name
	 */
	protected void property( DesignElement obj, String propName )
	{
		writeProperty( obj, null, propName, false );