Also added a “description” field for wiki folders.
Right now there’s too many editions listed. I think we should by
default only list editions whose `tiddlywiki.info` file has
`showInListings` set to `true`, and have an `--editions all` command
that lists everything.
@pmario please could you check that the editions in your
`TIDDLYWIKI_EDITION_PATH` are correctly listed?
We re-use some of the existing syncer mechanism. It was already keeping
track of changes to tiddlers in the store when working with a tiddler
syncadaptor. Now it also tracks changes when there is no syncadaptor,
allowing us to provide a warning if there are unsaved changes.
