Bug 111631 [Viewers] TreeViewer needs more TableViewer API
As the TreeViewer is meant to replace the TableTreeViewer we need to add some of the API that the TableViewer had to it so that it can be used like a table. public void insert(Object element, int position) public void add(Object[] objects) Both need to be added.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
* This method should be called (by the content provider) when elements
     * have been added to the model, in order to cause the viewer to accurately
     * reflect the model. This method only affects the viewer, not the model.
     * </p>
     * 
     * @param parentElementOrTreePath
     *           the parent element
     * @param childElements
     *           the child elements to add
     */
    public void add(Object parentElementOrTreePath, Object[] childElements) {
        Assert.isNotNull(parentElementOrTreePath);
        assertElementsNotNull(childElements);
        Widget[] widgets = internalFindItems(parentElementOrTreePath);
        
        if (widgets.length == 0)
            return;
		for (int i = 0; i < widgets.length; i++) {
			internalAdd(widgets[i], parentElementOrTreePath, childElements);
		}        
    }
    /**
     * Find the items for the given element of tree path
     * @param parentElementOrTreePath the element or tree path
     * @return the items for that element
     */
	private Widget[] internalFindItems(Object parentElementOrTreePath) {
		Widget[] widgets = findItems(parentElementOrTreePath);
        if (parentElementOrTreePath instanceof TreePath) {
			TreePath path = (TreePath) parentElementOrTreePath;