2.7.83 released May 1, 2000

- new functions in engine/interface.c
- p[][], ko_i, ko_j, black_captured, white_captured moved from gnugo.h
  to liberty.h, i.e. made local to the engine
- attack() and find_defense() also made local to the engine
- board handling functions removed from interface/interface.c
- all interface functions in interface/interface.c now use the Position
  datatype
- sgfAddMoveFromTree() and sgfPlayTree() moved from sgfana.c to ttsgf.c
- minor tuning of mouse_defendpats.db