By rearranging the `[all[]]` operator we are able to ensure that shadow
tiddlers get processed before ordinary tiddlers. This makes it easier
to create custom stylesheets that override the core.
We get a significant speed improvement of >10% by rearranging filter
operators to bring to the front the operators likely to reduce the size
working list.
Now we reserve the `title` class for the tiddler title span itself, and
`titlebar` for the previous purpose of identifying the div containing
the title and the toolbar buttons
Templates are the low-level bits and pieces that allow TW5 to generate
HTML and CSS renderings of tiddlers. The UI folder contains the
user-visible UI of TW5
