crux-00004: $SRC/utils

  utils/README.chk                      about the "chk" module
  utils/README.panic                    about the "panic" module
  utils/chk.h                           "chk" interface declaration
  utils/chk_free.c                      free(3) replacement
  utils/chk_i.h                         "chk" internals interface
  utils/chk_limit.c                     allocation limit
  utils/chk_malloc.c                    malloc(3) replacement
  utils/chk_realloc.c                   realloc(3) replacement
  utils/panic.c                         implementation of panic()
  utils/panic.h                         interface declaration