just a "somewhat more POSIX" but also a "/bin/sh legacy kludge" mode
* consistently capitalise POSIX and SUSv3/SUSv4 (same as AT&T ksh) and
Bourne shell
to it are now either arc4random or rand/srand, but srand retains the old
state; set +o arc4random is no longer possible, but if it's there we use
arc4random(3), if not, we use rand(3) for $RANDOM reads; optimise special
variable handling too and fix a few consts and other minor things
MKSH_S_EDIT for small (Emacs) editing mode, MKSH_S_FEAT for all the dis-
abled language features), which can be set to 0 despite MKSH_SMALL being
defined to re-enable the Vi command line editing mode (which I wouldn't,
but fits into the general mastermind scheme)
• shell flags are now handled in one single place (sh_flags.h)
• sync comments (between enum and array) and manpage with reality
• FMONITOR is now no longer needed for Hartz IV shells
