This requires Unicode icon support to be enabled via ED.
The ellipsis symbol is shorter and more distinctive, allowing more of the original
text to be preserved before truncation.

* Practically requires one of the "Nerd Font" fonts,
  so it's disabled by default.
  Add 0,512ED to the profile to enable them.
* The new ED flag could be used to control Gtk icons as well,
  but they are left always-enabled for the time being.
  Is there any reason anybody would like to disable icons in Gtk?
* The list of icons has been adapted and extended from exa:
  https://github.com/ogham/exa/blob/master/src/output/icons.rs
* The icons are hardcoded as presorted lists,
  so we can binary search them.
  This could change in the future. If there is any demand,
  they could be made configurable via Q-Registers as well.