- Add -output option to control output format.
- Add -format option to configure columns.
- Add option to search and/or print by "other keywords" from CLDR. Maybe also
  allow :cool: and such?
- Allow copying to clipboard. From HN comment
  https://news.ycombinator.com/item?id=21780608

   > `echo -n "$selected_symbol" | xclip -i`
   >
   > And then fake a middle click to insert in the current application:
   >
   > `xdotool click 2`o

  Also maybe send as direct input (xdotool can do this, but is apparently not
  reliable across all apps/characters).
