[International Draughts] PDN FEN tag support issues and limitations

[IgorLeMasson]

At 0.9.12 version these issues and limitations can be seen:

[1]. FEN tag is only displayed for game end position, if you select any other move, the respective tag is not shown.

[2]. Positions represented by PDN 3.0 FEN tags aren't displayed on board through the "Board state" either "Load board state" function buttons.
FEN tag example:
"W:W26,31,35,37,42,44,45,47,48,50:B4,8,9,10,16,17,18,19,29,34"