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
* Finds a named report item in this module and the included modules. This
	 * is for body elements in the element's name space.
	 * 
	 * @param name
	 *            The name of the element to find.
	 * @return The element, or null if the element is not found.
	 */
	public DesignElement findElement( String name )
	{
		return resolveNativeElement( name, ELEMENT_NAME_SPACE );
	}
	/**
	 * Finds a data source by name in this module and the included modules.
	 * 
	 * @param name
	 *            the name of the data source to find.
	 * @return the data source, or null if the data source is not found.
	 */
	public DesignElement findDataSource( String name )
	{
		return resolveElement( name, DATA_SOURCE_NAME_SPACE, null );
	}
	/**
	 * Finds a data set by name in this module and the included modules.
	 * 
	 * @param name
	 *            the name of the data set to find.
	 * @return the data set, or null if the data set is not found.
	 */
	public DesignElement findDataSet( String name )