TODO

* Port "fileman" example from BSD libedit, http://www.thrysoee.dk/editline/
* Instead of supporting multiline input, try the Emacs approach, line scrolling.
* Add support for rl_bind_key(), currently only en editline specific el_bind_key() exists.
* Add support for inhibiting completion: rl_inhibit_completion
* Make "char *rl_prompt" globally visible.
* Add support for rl_set_prompt().
* Add support for --enable-utf8 to configure
* Use strcmp(nl_langinfo(CODESET), "UTF-8") to look for utf8 capable terminal.
* Implement simple UTF-8 parser according to http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8