* Adds a name to the core plugin
* Make plugin listings consistently show "name: description"
* Make plugin listings consistently sort by title (thus grouping publishers)
* Add a missing plugin name
See discussion here: https://github.com/Jermolene/TiddlyWiki5/pull/4508#issuecomment-609671970
We were unpacking plugin tiddlers in arbitrary order, and ensuring that
later plugins didn't overwrite shadow tiddlers from earlier plugins.
Now we'll allow plugins to specify a "pluginPriority" that determines
the load ordering. We also explicitly allow shadow tiddlers from later
plugins to overwrite shadow tiddlers from earlier plugins.
We're setting a base priority on the core plugin, since many plugins
will want to control their loading relative to it.
