Bug 154178 Support projectFolder in BIRT viewer
If the report supports projectFolder, the viewer also need to enhance for this feature.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
/**
	 * URL parameter name that gives the page number to display the report.
	 */
	public static final String PARAM_PAGE = "__page"; 
	/**
	 * URL parameter name that gives the report design name.
	 */
	public static final String PARAM_ISNULL = "__isnull"; 
	/**
	 * URL parameter name that determines to support masterpage or not.
	 */
	public static final String PARAM_MASTERPAGE = "__masterpage"; 
	/**
	 * URL parameter name that determines whether the BIRT application is
	 * running in the designer or standalone.
	 */
	public static final String PARAM_DESIGNER = "__designer"; 
	/**
	 * URL parameter name that determines whether to overwrite the document or
	 * not.
	 */
	public static final String PARAM_OVERWRITE = "__overwrite"; 
	/**
	 * URL parameter name that gives the image ID to display.
	 */
	public static final String PARAM_IMAGEID = "__imageID"; 
	/**
	 * URL parameter name that gives the bookmark expression.
	 */
	public static final String PARAM_BOOKMARK = "__bookmark";