Bug 122850 Table/list should not be able to be inserted in Master Page mode.
Description: Table/list should not be able to be inserted in Master Page mode. Steps to reproduce: 1. New a report and transfer to Master Page mode. 2. New a datasource and dataset 3. Drag a list/table to page header/footer, bind it to dataset and drag some columns inside. 4. Save and preview Expected result: Insert list/table item in master page should be forbidden. Actual result: They are allowed and preview showed "undefine" in page
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/Module.java
*/
	public boolean isReadOnly( )
	{
		return activityStack instanceof ReadOnlyActivityStack;
	}
	/**
	 * Adds one attribute listener. The duplicate listener will not be added.
	 * 
	 * @param listener
	 *            the attribute listener to add
	 */
	public void addAttributeListener( IAttributeListener listener )
	{
		if ( attributeListeners == null )
			attributeListeners = new ArrayList( );
		if ( !attributeListeners.contains( listener ) )
			attributeListeners.add( listener );
	}
	/**
	 * Removes one attribute listener. If the listener not registered, then the
	 * request is silently ignored.
	 * 
	 * @param listener
	 *            the attribute listener to remove
	 * @return <code>true</code> if <code>listener</code> is successfully
	 *         removed. Otherwise <code>false</code>.
	 * 
	 */
	public boolean removeAttributeListener( IAttributeListener listener )
	{