protected boolean isReplaceAllowed(int rowIndex, DataType dataType) {
		return false;
	}
Moves a contiguous selection of components down by a single position. The component that was
immediately below (at the index immediately following the selection) the selection will be
moved above the selection (to what was the minimum selected component index).
@return true if selected components were moved down.
@throws UsrException if components can't be moved down.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/compositeeditor/CompositeEditorModel.java