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/api/ModuleHandle.java
/**
	 * Returns a list containing warnings during parsing the design file.
	 * 
	 * @return a list containing parsing warnings. Each element in the list is
	 *         <code>ErrorDetail</code>.
	 * 
	 * @see ErrorDetail
	 */
	public List getWarningList( )
	{
		return module.getWarningList( );
	}
	/**
	 * Returns the iterator over all embedded images of this module instance.
	 * Each one is the instance of <code>EmbeddedImageHandle</code>
	 * 
	 * @return the iterator over all embedded images.
	 * 
	 * @see EmbeddedImageHandle
	 */
	public Iterator imagesIterator( )
	{
		return getPropertyHandle( IMAGES_PROP ).iterator( );
	}
	/**
	 * Returns the list of embedded images, including the one from libraries.
	 * Each one is the instance of <code>EmbeddedImageHandle</code>
	 * 
	 * @return the list of embedded images.
	 *