message: Fix pygtp coords.
diff: @@ -9,7 +9,7 @@ Flattened Coordinate: this is a number ranging from 0 - N^2 (so N^2+1
  SGF Coordinate: Coordinate used for SGF serialization format. Coordinates use
  two-letter pairs (r,c) indexed from the upper-left (aa).
  KGS Coordinate: Human-readable coordinate indexed from bottom left.
  -GTP Coordinate: Tuple coordinate indexed starting at 1,1 from top-left (r, c)
  +PYGTP Coordinate: Tuple coordinate indexed starting at 1,1 from top-left (r, c)
  So, for a 19x19,
  @@ -19,7 +19,7 @@ minigo coord (0, 0) (18, 0) None
  flat 0 342 361
  SGF 'aa' 'sa' ''
  KGS 'A19' 'T19' 'pass'
  -GTP (1, 1) (1,19) 'pass'
  +pygtp (1, 19) (19,19) 'pass'
  """
  import go
  