* Add warning in document tiddler toolbar if tiddler already exists
* Live preview document in new window
* Fix slicer.js bug that was preventing the list field of headings from
being filled in correctly
* Rationalise some class names
Now includes a special document view column on the left. Headings can
be expanded/collapsed, and tiddler titles can be inspected and renamed
via the toolbar. Clicking on an entry opens the associated tiddler. The
default tiddler view template includes a special section for tiddlers
that are part of a document
Now we process the rendered HTML of tiddlers, which allows us to
process HTML generated by MS Word. In fact, the HTML that MS Word
generates is so awful, I’ve instead been using Mammoth to do the
conversion: https://github.com/mwilliamson/mammoth.js
Also some necessary improvements to the fake dom implementation.
1. Introduce template tiddlers for the document, each tiddler, and the
tiddler toolbar
2. Move the text slicer toolbar button to the left of the edit button
3. Add a selectable toolbar, currently just containing the tiddler title
