Comment format
==============

Comments in openings.pgn are a list of opening names for that move.  If several
names are known, they are separated by a semicolon.  

Name are written in sentence capitalization. 

The complete opening name is found by concatenating all comments in the current
move list, e.g.:  After 1.e4 c5, the comment is "Sicilian Defense" and after
1.e4 c5 2.Nf3 Nc6 it's "Nimzovitch Variation".  The full opening name will then
be "Nimzovich Variation, Sicilian Defense". 

Each opening name may begin with:

* An asterisk indicates that the opening name is overidden by a name that comes
  later in the game.  E.g.:  1.e4 is called "King Pawn Game", but after 1...c5
  the opening is called "Sicilian". 

+ A plus sign "eats" previous opening names.  E.g., 1.e4 e5 2.Nf3 Nc6 3.Bc4 is
  "Italian Game", but after that 3...Nf6 is "+Two Knights Defense", because the 
  resulting game is never called an italian game. 

COMMENT = [ "+" | {"*"}] NAME { ";" NAME }
NAME    = _ "(" STRING ")" |
	  TYPE "(" NAME ")"   
TYPE    = <see source>



