XSB Src (SVN)-old

Small change to test out cvs commit from home.

Fixed some inefficiencies in compiler/parser due to frequent use of
atom_codes.

fixed bugs related to tracing aggregates.

added xsb_sprint_variable to fix the problem with printing vars in
print_pterm: cinterf.c (now fmt_write('%S', f(V)) prints vars the same
way as write(V) does).

Prevent backtracking over the print function hook

Changes in the general unification routine to speed up unification;
around 10-20% for some programs; courtecy of Bart Demoen and Kostis
Sagonas.

Enabled tracing of findall, call.

Fixed proglems with Redo and uninstantiated vars in the debugger.

small things

clean up sockets interface in minor way. Eliminate socket flush.