chat:
- remove table-based renderer for polled mode;
   we use now always (in polled, streaming and
   scripted-streaming mode) div-based message layout
- extend ::xowiki::Chat login by an option "-path"
   to make sharing of ajax-files simpler in derived
   packages (e.g. xowf)
- added includelet "chat"
- added utility function "xowiki::utility user_is_active" to centralize logic about querying and rendering active users
menu-procs:
- refactor "update_items" from folderprocs to make
  in generally usable

folder-procs:
- added modifying user to includelet "child-resources"
   (can be decativated via "-hide ...")
- added optional menubar for adding content to the folder
   managed by "child-resources"
- update dependencies and bump version number to 0.146
- pretty_link: fall back to the toplevel url of a package in case no parent_id is provided
- no need to pass parent_id to page-based pretty_link
- make oacs-view3 (as used on openacs.org) more robust
- minor html optimization
- pretty_link: no need to call method, since $name is available
- minor cleanup
- initialize options to improve robustness for subclassing