[BusyBox] clean Bourne shell parser, under construction

[larry at doolittle.boa.org]

I just put a fresh version of parser.c at
   http://doolittle.faludi.com/~larry/parser.c

Redirects and $* "work", null arguments are detected and handled
correctly.  The to-do list is just about as long as it was on
Dec 23, but that's really an indication that I know more about
the scope of the problem.  If people chip in and help (like Erik
has a little already), we could easily have a "real" Bourne
grammar for BusyBox in a week.

      - Larry

P.S., with debug_printf disabled, the executable size is right
at 8K.  This is only the parser, which is the subset of the existing
sh.c functionality that fills in struct job and friends.