XSB Src (SVN)-old

Changed semantics of predicate_property/2 w.r.t. tabling properties to make things more
consistent and hopefully clearer. Also restructured the code of this predicate.

Took care of the cases of

table p/1 as dynamic

that I could locate -- there may be more.

Updated predicate_property/2.

Fixed problem with

:- table p1/1 as dyn.
or
:- table p1/1 as (dynamic).

This worked as a directive, but does not work as a declaration in a
compiled file where clauses for p1/1 are defined. The problem was
that the compiler didn't immediately set the property dynamic for
p1/1, so that the clauses were compiled statically. If clauses for
p1/1 weren't defined, things worked, since the directive dynamic p1/1
would be executed when the file was loaded, so assertions of p1/1 gave
no problem.

Fixed bug in executing table p/1 as dyn.

Minor refinements: special case some operations for efficiency (reindex)
and a little more checking for input errors.

Re-added tests that were inadvertently deleted.

New tests for new functionality in prolog_db module.

New predicates for cross product, join, reindex, and project that work directly
on trie databases.

Addition of answer subsumption as an inspectable table property.