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/Module.java
* @return true if the file exists, false otherwise.
	 */
	public boolean isFileExist( String fileName, int fileType )
	{
		URL url = findResource( fileName, fileType );
		return url != null;
	}
	/**
	 * Gets a list containing all the include libraries.
	 * 
	 * @return a list containing all the include libraries. Return
	 *         <code>null</code> if there were no include libraries defined.
	 */
	public List getIncludedLibraries( )
	{
		return Collections.unmodifiableList( (List) getLocalProperty( this,
				LIBRARIES_PROP ) );
	}
	/**
	 * Gets the default units for the design.
	 * 
	 * @return the default units used in the design
	 */
	public String getUnits( )
	{
		if ( !StringUtil.isBlank( units ) )
			return units;
		return (String) getPropertyDefn( UNITS_PROP ).getDefault( );
	}
	/**