* Default generated for new users (oputil.js tool to come)
* Defaults to setting ActivityPub image/icon
* Allows ops to configure the look, extend, etc.
* Deprecated explicit prompt.hjson/general.promptFile, etc.: menu.hjson can simply include any number of files
* All menus and themes, their events, etc. are managed by ThemeManager allowing includes, refs, etc. and much cleaner code