XSB Src (SVN)-old

Added a new test of SDG printing and fixed a bug in SDG morphisms.

A few updates to inspection.tex, although there is plenty left to do.

Factored out libraries borrowed from other Prologs. Also I commented
out the justification section as this is not being maintained, and we
arguably have better debugging methods now.

Since I needed to use AVL trees, I took a few minutes out to document assoc.P, the libary that contains this functionality.

Initial test for tripwires.

Initial commit for tripwires

Initial commit for tripwire handling for large number of subgoals / large number of SCCs.

Micro optimization of lattice and fold aggregation in case of all true
answers. This gives maybe a 5-8% improvement in time for intensive
aggregations of true answers.

Fixed aggregation so lattice and fold now work with undefined answers.
This restores the functionality that Teri introduced, but in which we
found a bug. It also extends it to fold. It detects if no undefs
occur and uses the earlier more efficient version in that case. There
is some overhead for the checking but it is small compared to always
assuming undefineds occur.

It should be noted that producing all possible undef answers can be
combinatorically explosive, so care should be taken when using this
option.

Removed code that hasn't been used in years (old_excess_vars/4)