Add MiniPlaceholders for leaderboard and etc.

[jpenilla]

[perlsol]

I would love to show placeholders like a top 10 scoreboard please, with playername, and number of games played. %chesscraft_topplayers_[1-10]%

and another top 1 board... maybe also a top 10 for games won in quickest time and the ability to show how many moves %chesscraft_toptime_[1-10]% %chesscraft_toptime_moves_[1-10]%