XSB Src (SVN)-old

Added getMemorySize.c

Added sys_main_memory/1.

Changes to fix sysint problem

Changes for get_memory_size

Adding new file

Made temp tabled predicate to be opaque, to avoid issues with
incremental tabling. This breaks nothing in the testsuite.
(Teri should confirm it's the right fix.)

Minor changes in ac_tests (for easier benching.)
Minor change in delay_var, not to precall with cross-product, that I noticed
when tracing. Change mainly for clarity.

Changed way that answer-completion knows it's done: now uses simplification
flag set by completion to know that another iteration will give the same
result.

1. Added flag that indicates if simplification was done during completion.
It is used in answer_completion to avoid an extra iteration.
2. Improved (I think) building of delay lists (for get_residual), to be
slightly more resilient to heap movement in GC.

Eliminated several wasted cells on the heap (i.e., hreg was over-incremented.)