Add options to use feed names from newticker-url-list

Add options to use feed names from newticker-url-list

* lisp/net/newst-treeview.el
  (newsticker-treeview-use-feed-name-from-url-list-in-treeview): New.
  (newsticker-treeview-use-feed-name-from-url-list-in-itemview): New.
  (newsticker--treeview-item-show): Show feed name from
  newsticker-url-list if wanted.
  (newsticker--treeview-propertize-tag): Add argument 'tooltip'.
  (newsticker--treeview-tree-get-tag): Usefeed name from
  newsticker-url-list if wanted.  (Fixes third issue in
  Bug#41376.)