Bug 188027 PasteAction is diabled
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/Module.java
* Sets the module is read-only one. That means any operation on it will
	 * throw runtime exception.
	 */
	public void setReadOnly( )
	{
		activityStack = new ReadOnlyActivityStack( );
	}
	/**
	 * Returns the module namespace. Only included library has a non-empty
	 * namespace.
	 * 
	 * @return the module namespace
	 */
	public String getNamespace( )
	{
		return null;
	}
	/**
	 * Loads css with the given css file name. This file name can be absolute or
	 * relative. If the css doesn't exist or fatal error occurs when opening
	 * css,.
	 * 
	 * @param fileName
	 *            css file name
	 * @return the loaded css
	 * @throws StyleSheetException
	 */
	public CssStyleSheet loadCss( String fileName ) throws StyleSheetException
	{
		try