On selection of nodes in tree, the corresponding HTML div will now be highlighted.
When double clicking a node in the tree, the node will open to show its children.

preliminary work begun on selecting a node on the tree when HTML is clicked.
updated style to support highlighting of selected nodes
removed accordian wrapper divs.  document tree and 'insert inline element' space are both displayed all the time
updated styles to support highlight of HTML elements on selection.  some other style improvements
unordered and ordered lists no longer require titles
commented out inclusion of theme styles
clicks on the HTML / editing interface are now accompanied by selection / node opening on the Document Tree.