GNU Go 3.1.22 released January 20, 2002

This version will be faster because computation of owl threats
is turned off by default. There are three compile time options
worth mentioning

--enable-owl-threats             compute owl threats
--enable-experimental-semeai     use new semeai module
--enable-experimental-influence  use Arend's experimental influence

The first two options should result in more PASS'd tests,
and presumably make the program slower at the expense of speed.
I hope the experimental semeai can become the default after
Zobrist hashing gets implemented. I'm working on this.

There are a *lot* of changes to test results, 118 unexpected PASS
and 63 unexpected FAIL. Much of this is due to the patch gunnar_1_22.4.

Patches in this release:

arend_1_22.4. Experimental influence. 
trevor_1_22.5. Tuning. 
owl_1_threats_22.1. Owl threat computation made optional. 
arend_1_22.2. Tuning etc. 
gunnar_1_22.6. Filllib improvement. 
dfa_1_22.1. Makes dfa the default. 
trevor_1_22.3. Test case revisions. 
trevor_1_22.4. Various changes. 
komaster_1_22.1. Bugfix. 
teun_1_22.1. Rot revision. 
arend_1_22.3. New NNGS tests. 
gunnar_1_22.5. Tuning and new connection tests. 
gunnar_1_22.4. Atari_atari revisions. 
gunnar_1_22.3. Optics improved. 
arend_1_22.1. Redundant move reasons. 
trevor_1_22.1. engine.dsp. 
gunnar_1_22.2. Various small changes. 
gunnar_1_22.1. Revision of lazarus.tst. 
dfa_1_22.1. Increased DFA_MAX_MATCHED. 
sgf_1_22.1. Bugfix in sgftreeAddStone. 

- find_backfilling_move() in filllib.c revised
- dfa made standard
- owl threat computation made optional (and not default)
- comments added, cleanup around discard_redundant_move_reasons
- new (unused) experimental influence configure and run time options
- unsafe tactical moves now taken care by discard_redundant_move_reasons
- FIXME added for reevaluate_ko_threats
- atari_atari_attack_patterns() uses a goal array to limit search area
- new functions compute_aa_values(), get_aa_value(), and update_aa_goal()
- ko contingent defenses excluded in get_saved_worms(), get_saved_dragons()
- valuation of atari_atari move reasons revised
- recognize_eye() revised
- spelling corrections
- fflush() added a few places
- owl tries tactical defense for small groups
- owl logs number of variations per sub-tree in SGF file
- [ox]play_(attack_either|defend_both) handles ko correctly.
- added [ox]play_connect and dis_connect helpers
- allow followup value if defense threat is contingent on ko.
- only allow territory move values if move is deemed safe.
- reduce cutstone values in case of ko.
- debug printing in influence.c slightly restructured
- new function influence_moyo_color_opposite()
- one trace output reenabled in confirm_safety()
- bugfix in sgftreeAddStone
- bugfix in komaster_trymove
- mascot in dragon.c
- tuning
- eye tuning
- atari_atari tuning
- connection tuning
- fuseki tuning
- owl tuning
- test revisions