TODO (458B)
vt emulation
------------
* double-height support
code & interface
----------------
* add a simple way to do multiplexing
drawing
-------
* add diacritics support to xdraws()
* switch to a suckless font drawing library
* make the font cache simpler
* add better support for brightening of the upper colors
bugs
----
* fix shift up/down (shift selection in emacs)
* remove DEC test sequence when appropriate
misc
----
$ grep -nE 'XXX|TODO' st.c