* wait for error.[hc] that can include the other/be included by the other
  or swich to err.[hc] (also switching to err())
* maybe make lines.[hc] with getlines, sortedp permute & c. instead of
  getlines.[hc] and sortedp.[hc]
* install bogosort as unsort aswell, make argv[0] = "unsort" imply --nosort.
* fix output in configure test of sys_errlist
