didn't correctly start background jobs anymore. Strange that nobody
was complaining...
Add a dummy target for `builtins' in the Makefile, to prevent it
from attempting to build this file by compiling builtins.c. :-/
The && and || tokens do also terminate a command, not only the
newline.
While i was at it, disabled trace code by default, it served no good
purpose since it required the use of a debugger anyway to be turned
on. Instead, placed a hint in the Makefile on how to turn it on.
This makes the shell ~ 10 % faster and ~ 4 KB smaller. :)
Pointed out by: jan@physik.TU-Berlin.DE (Jan Riedinger)
automagically. -lfoo has to be right to work, but ${LIBFO0} is too
easy to forget or misspell; nothing checks it and it should be
different for shared libraries.
