21st-January-2018: TiddlyWikiTweaks

Figure out how to add a title or alt text to transcluded image tiddlers, possibly via an alt or title field and field value ($:/core/modules/widgets/image.js should let us do this)

This is useful for making the SVG title image accessible. Creating this feature is a bit too over my head, as it requires following the thread of src and deciphering what is and is not essential to my creating an optional feature. However, there is some precedent for optional features, as the TiddlyWiki docs show a couple of different, non-essential parameters. Follow those threads, duplicate and remix them.