dfa-2.11:
	- fixup a little bug: borders constraints now always checked.
	Now a pattern match on the board if and only if it is accepted by
	the dfa!
	- add experimental check_pattern_light() function only checking
	classes and goals. (does not seem to speedup a lot pattern matching).
dfa-2.10:
	- environement variable $GNUGO_PATH used if defined.
	- fixup portability bug
	- fixup for owl_vital_apats.db 
dfa-2.9:
	- Fixed an horrible bug in dfa.c: gpout was not
	cleanly reset before synchronization product this correction
	saves a lot of room!!
	- if DFA_SORT is set in new_matchpat.c then patterns are sorted
	before being sent to check_pattern to keep exacly the same order
	as it was in the old pattern matcher.
	- new experimental stat functions:
		  - update_pattern_stats() 
		  - display_pattern_stats()
		  - reset_pattern_stat() 
	- dfa_add_pattern is now able to add all transformations of
	a pattern into the dfa.
	- new functions (used by dfa_add_pattern):
		- permut() : compute transformation of edges constraints.
		- show_pattern_instance() : debug.
	- fixed some bugs in matcher.c, and matchtest.sh
	- removed some unused files.
	- option -tm force the anchor to be in the center and add all 
	transformations in the dfa the result is a speedup of
	pattern matching at the cost of a bigger dfa. This option is
	still alpha.
	- added little_owl.tst to check the pattern matcher in 
	less than one hour.

dfa-2.8:
	- removed wrong and unused part of mkpat.
	- dfa.c file #included in new_matchpat instead of copy/pasted
	- new function dfa_add_pattern (still under construction):
		 - board_to_string() : create a string from a given 
		 instance of a pattern.
dfa-2.7:
	- fixed warning "conn.c:1526: warning: missing initializer"
	- new value in dfa_t : all_trans
	- new option -t in mkpat : add one entry by transformation in dfa:
	  this should speedup a lot the pattern matching but enlarge the dfa.
	
dfa-2.6bis.c:
	- new_mkpat add a dfa_t pointer when DFA_ENABLE is set to 1.
	- little change in function load_dfa : load_dfa(file_name, NULL)
	return a pointer to a newly created dfa_t struct if file_name was 
	found or NULL if file_name was not found 
	( dont forget to free this struct).
	- some cleaning in all files to avoid a lot of message when 
	compiling with -Wall (unused variables for eg.)
	- made more functions static.
	- forward declaration for all functions (more readable).
	
	
dfa-2.6.c:
	- new function dfa_compile_for_match()
	copy the board into a private board, changing the colors
	on the way.
	- modified read_board() to use the private board dfa_p.
	- new function dfa_restart()
	- new function dfa_scan(), the scanner !
	- new parameter DFA_TRACE to trace while scanning.
	- new file matcher.c: a test file for the matcher.
	- new test file dummy.db
	- test script matchtest.sh.
	- test-dfa, dummy.c and TEST.README no longer used.
			
dfa-2.5.c:
        - on demand resize system in all dfa functions:
          To avoid heavy resizing with cosmic heuristics used in
          preceeding versions, the dfa are automatically resized 
          when more space is needed.
        - new_dfa() no longer need size arguments.
        - fixed the MAX_BOARD bug:
        - replaced the ambigous MAX_BOARD by DFA_MAX_BOARD
        - fixed the "alloca" bug:
          use of malloc instead of alloca in sync_product(): 
          as said in the libc documentation about alloca,
          "If you try to allocate more storage than the machine can provide,
          you don't get a clean error message.  Instead you get a fatal
          signal like the one you would get from an infinite recursion;"
        - renamed some parameters in dfa.h to improve the readability.
        - dfa_add_string uses two new arguments: max_Kb_size and 
          max_Kb_increase. The string is only added if the new size 
          ( after sync. product) is lower than max_Kb_size and if the 
          increase of size is lower than max_Kb_increase. The function
          return the new size of the dfa. 
          this allows mkpat to generate dfa near the expected size 
          option -d<mem> ).
        - dfa_add_string alway accept one char strings.
        - option -r changed from ratio system to increase system.
        - removed ratio system from write_to_dfa();
        - increase computed as a ratio from the remaining memory.
        - -m option tell mkpat to place (if possible) the anchor 
          in the middle of the pattern as it may decrease the size 
          off generated dfa's (sometimes not).
        
dfa-2.4.c:
        - renamed dfa-2.3.c into dfa.c
        - bigTest.sh test generate some dfa's from .db files
        but still bugs on patterns.db
        - test-dfa loads some generated dfas.
        - worked on the memory management (still too bad).
        - fixed a lot of stupid bugs.
        - new tuning options in new_mkpat:
                -V <level> = dfa verbose level
                -r <ratio> = heuristic tuning

dfa-2.3.c:
        - bug fixed in build_spiral_order()
        - new functions dfa_init() / dfa_end()
        - new functions dfa_add_string()
        - new function pattern_2_string() : Convert a gnugo pattern 
        structure info a dfa string and compute some heuristics.
        - one bug fixed in sync_product.
        - dfa-2.3.c splitted into 3 files : dfa.h test-dfa.c dfa-2.3.c
        
        - added dfa_verbose system (don't know if it is usefull)
        - added some debug patterns (dummy.c) --> obslolete.
        
        - .dfa generation in mkpat with option -d <mem>
        where <mem> is the maximum size in Mb allowed for the dfa
        /* not really working for the moment */
        - fixed some old bugs an added a lot of new bugs.

dfa-2.2.c:
        - added #include <string.h> for portability.
        - added some standard gnugo #defines.   
        - attribute lists do not use absolute pointers but integer indexes.
        - new function dfa_copy()
        - Spiral order with 8 geometric transformations.
        - new function read_board() /* not tested for the moment */
        - some cleaning in the main torture test function.
        - added a test script with many patterns.
        - support for empty strings for pattern we want to match every time.
          This allow us easily to deal with memory if we do not want a too 
          big dfa.
        - Two new functions load_dfa /save_dfa to save dfa's on binary files 
          for transmission from mkpat to matchpat.

dfa-2.1.c:
        - Memory allocation in dfa for attributes.
        - Spiral order generation

dfa-2.0.c:
        - Total rebuild from dfa-1.2.c
        - Use of synchrone product of dfa's and attribute sets

TODO:
        - function do_dfa_matchpat in new_matchpat.c (easy).
        - loading of dfa's in new_matchpat.c
        



        
