Log Message:
Update to 1.5.0

  Add new function pr_open2 with argument "callback" ran from child
  process immediately after fork(2) and before execvp(3).

  COPTS defaults to -O2 -g

  Add support for target "help", bump MKC_REQD to 0.34.0

  maa/log.c: fix compilation failure due to -Werror on NetBSD-10.99.10
  with gcc-10.5.0

  Move WARNS=4 to Makefile.common

  SUBPRJ_DFLT = maa test

  MAXHOSTNAMELEN can be already defined, limit to 64 characters to
  avoid possible truncation.