(1) Shift-left code from templates, to compensate for script tag padding.
(2) Added JavaScript tags, to support upcoming JavaScript Lab.
(3) Eliminated the need for the templateId attribute, by moving the script/template tag into the body of the Example tags.
(4) Simplified the tags (e.g., eliminated all block tags, eliminated the css-html example tag and splitting it into separate css and html example tags).
(5) Other misc cleanups.