Mostly, changes for AWLF:

1. Inserted wlbscnf call before SAACYC

2. Implemented cube-slicing in AWLF.
   (Currently disabled, but code is there. The slicing is not
   performed properly in cases where the index vector axes
   are permuted or duplicated, such as in transpose (j,i) or major
   axis selection (i,i).

3. Killed FLATG before SAACYC.

4. Introduced PRFUNR extensions for extrema propagation, post-Loch Ness.
   We now unroll vector_based guards into scalar-based guards.

5. Made extrema N_avis sons, rather than attributes.
   This corrected a fair number of mystery crashes.

6. We now propagate extrema, minima and maxima, independently.

7. Insert SAA AVIS_SHAPE/DIM information within SAACYC now.
   Previously, this was performed only before SAACYC, and each
   optimization was responsible for maintaining SHAPE/DIM
   information itself.

8. Optimizer maintenance of SAA information (item 7) deleted with 
   #ifdef statements, for the nonce, on the assumption that
   item 7 will do the job now.

9.  Introduced CF optimizations for guards.

10. Introduced CF optimizations for extrema.

11. Introduced symbiotic expressions using sacprelude functions
    for AWLF intersect computations.

12. Moved stabilization cycle after SAACYC.
    Placement of this, and of traversals within SAACYC,
    should be vetted.

13. Introduced VP into SCYC to make IVESPLIT work again.

14. Introduced LS into SAACYC, to address Bug#697. See Bugs #709, #710.

15. Introduced scalar constraint/guard functions, for post-Loch Ness AWLF.

16. Fixed WLSIMP AVIS_SSAASSIGN bug.

17. IVE changed to flatten idx2offset and/or vect2offset nodes. This
    was required to make TC/CF, etc., at the end of phase 11 work
    properly. VP/CP at end of phase 11.

18. Added include for globals.h to prepare_inlining.c, to correct
    compilation error.

Known problems:

 - Many rbe-induced warnings during compilation, which I will fix up
   soon. 
 - LIR failure still causing severe performance losses. sah has this
   in hand.
 - AS failures cause AWLF to fail on relatively simple codes, e.g.,
   gauss.sac in awlf test suite.
   Since AS no longer exists, this is not surprising. I will
   attempt its revival, since symbolic CF can not do the job
   unless operands are shuffled.
 - I am of the opinion that stdlib take() and perhaps drop()
   generate bad code for negative take counts. That causes
   sac/apex/UTThornBoolean/UTThornBoolean.sac to crash when compiled
   with -ecc, with an error message that is correct, but which
   requires the user to be able to read IL in order to isolate.
 - I would appreciate code review/inspection of any/all of these
   documents. In particular, anything labeled FIXME should be
   checked.
 - -check c will fail for some newly introduced scalar guards. 
   There is something wrong memory/alloc.c for these guards,
   and the module does not offer any guidance on writing code
   for new primitives.
 - ct_prf.c: fails to completely typecheck some new guards,
   I think. Same problem as with -check c: no docn in code.