XSB Src (SVN)-old

Changes were mostly for documentation and code refactoring.

However, also fixed a latent bug in simplification where
was_simplifiable was not properly checking negative delay elements
corresponding to subsumed subgoal frames. This led to the possibility
of adding un-needed delay elements that might not have been simplified
away. Surprisingly enough, however, none of the tests in the test
suite checked for this.

Adding a new test for copying attributed variables into delay elements
/ lists. I hadn't thought this worked, but apparently it does !

Also, I'm adding a very simple test for incremental evaluation -- more
cases need to be added here, but at least this is a start.

adding dret_test.P to subsumptive tests.

Adding a new test for copying attributed variables into delay elements
/ lists. I hadn't thought this worked, but apparently it does !

Also, I'm adding a very simple test for incremental evaluation -- more
cases need to be added here, but at least this is a start.

Fine tuning for exclude tests (to run call subsumption tests under batched).

Updating a number of files so that delete_branch() will work with call
subsumption (it needs to know that it deallocates BTNs rather than
TSTNs). This fixed a latent bug in simplification and allows another
test to be run for call subsumption. It also provides a step towards
supporting answer subsumption on call subsumptive tables. There are
also some other documentationstyle changes.

Adding a new test for copying attributed variables into delay elements
/ lists. I hadn't thought this worked, but apparently it does !

Also, I'm adding a very simple test for incremental evaluation -- more
cases need to be added here, but at least this is a start.

Fixed so that batch test tests only neg_tests for subsumption. Still
need to fix delay_tests and wfs_tests to work under batched.

added a missing } to is_number_atom

Also, took out restrictions that predicates that use call subsumption
cannot delay.

tr_utils.c -- fixed bug for abolish_all_tables in mt engine that
showed up when running some subsumption tests on mt engine. Now the
mt engine runs the sequential test suite in the same way as the
sequential engine.

slgdelay.c -- minor changes to get rid of compiler warnings.

Changes to get rid of sloppy extern statements, and put them into a .h file where they should be.