Bug 153853 [Regression]The bound column names must be unique within the entire table.
Regression case Regression_136421(under org.eclipse.birt.report.tests.model) failed. Expected result: Model will avoid adding a duplicate bound column name within a table.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ModuleHandle.java
* @throws SemanticException
	 */
	public void shiftScriptLibs( int sourceIndex, int destIndex )
			throws SemanticException
	{
		ElementPropertyDefn propDefn = module.getPropertyDefn( SCRIPTLIBS_PROP );
		PropertyCommand cmd = new PropertyCommand( getModule( ), getElement( ) );
		cmd.moveItem( new CachedMemberRef( propDefn ), sourceIndex, destIndex );
	}
	/**
	 * Add script lib
	 * 
	 * @param scriptLib
	 *            script lib
	 * @throws SemanticException
	 */
	public void addScriptLib( ScriptLib scriptLib ) throws SemanticException
	{
		ElementPropertyDefn propDefn = module.getPropertyDefn( SCRIPTLIBS_PROP );
		if ( scriptLib == null || StringUtil.isBlank( scriptLib.getName( ) ) )
		{
			throw new PropertyValueException( getElement( ), propDefn,
					scriptLib,
					PropertyValueException.DESIGN_EXCEPTION_INVALID_VALUE );
		}
		
		PropertyCommand cmd = new PropertyCommand( getModule( ), getElement( ) );
		cmd.addItem( new CachedMemberRef( propDefn ), scriptLib );
	}
}