Bug 152828 Add the projectFolder property on module
When user doesn't set the resource folder path in designer, there should be a default working path for Birt to manage the report design and find the related resources. A new property should be added on Module: name: projectFolder type:URL This property only can be given from the open design method from session but should not be set after the module initialized. Concern about the backward compatiblity issue, a new method will be added. Open design with a config argument.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignSession.java
*/
	protected ULocale locale;
	/**
	 * The resource bundle for the user's locale.
	 */
	protected ModelResourceHandle resources;
	/**
	 * The units of measure used by the application.
	 */
	private String units = DesignChoiceConstants.UNITS_IN;
	/**
	 * RGB display preference for color properties used by the application;
	 */
	private int colorFormat = ColorUtil.CSS_ABSOLUTE_FORMAT;
	/**
	 * The application-specific default values of style properties.
	 */
	private HashMap defaultValues = new HashMap( );
	
	/**
	 * Resource change listener list to handle the resource change events.
	 */
	private List resourceChangeListeners = null;
	/**
	 * Constructor.
	 * 
	 * @param theLocale
	 *            the user's locale. If null, use the system locale.
	 */
	public DesignSession( ULocale theLocale )